Diono Monterey XT Review

Diono started in 1999 in Seattle Washington. In 2002, they won an award for the creation of the Diono Mighty-Tite. Inspired by their win, established its first overseas operation in Staffordshire, England. In 2005, they launched the Radian Convertible Car Seat, the first steel-reinforced folding car seat. In 2007, they launched the Monterey which went on to win multiple awards. In 2015, Winona Capital invested in Diono to help them grow and develop new and innovative products.

Performance Comparison

The Diono has thick EPS foam in the headrest presumably for additional protection in the event of a side impact collision.

Credit: Abriah Wofford

Crash Test

The Diono earned a better than average score for crash test results. We considered any booster that scored above the average as having a potentially higher margin of safety compared to the lower scoring options. This is one of the few that performed similarly well for both sensors as opposed to good data from one and less impressive from another or below average for both.

This graph is a comparison of the Diono's Head Impact Criteria (HIC) score of 556 (black) and the UPPAbaby Alta's 390 HIC (green) the best data for the group (a lower HIC score is better).

Credit: MGA, BabyGearLab Staff

The Diono data for the head sensor (HIC) is 556. The maximum allowed is 1000 (where a lower result is better), so it is well below the maximum and better than several other seats we tested. The low for the group is 390 earned by the UPPAbaby Alta.

This graph is a comparison of the Diono data for the chest (G) sensor (black), which earned it a Chest Clip score of 42, which was only a bit higher than the best performing seat on chest forces, the Peg Perego Viaggio Flex 120 (green) which had a 39 Chest Clip score, the best data for the group (lower is better).

Credit: BabyGearLab, MGA Research

The Diono chest (g) sensor result is 42. The maximum allowed to pass safety regulations is 60 where a lower result is better. The best in the group is the Peg Perego Viaggio Flex that earned a 39. The high is 48 so the Diono is both below the max and much lower than the high for those boosters we tested.

The Diono was easy for little testers to use on their own.

Credit: Abriah Wofford

Ease of Use

The Diono is relatively easy to use compared to the competition. This booster is easy for children to use by themselves with retainers that keep the belt properly positioned and a design that makes buckling themselves in easier.

This booster can be installed using LATCH anchors to keep it from moving freely about the car. The anchors are the clip style (above left) that can be harder to use, but the front tightening straps (above right) make the process easier.

The shoulder strap retainer that you use when the back is off can be somewhat difficult to push into the retainer (above left) but once it is on the belt it works well and stays on the belt (above right).

The width of the Diono can be adjusted using a knob on the back of the seat (above left), it is easy to use, but you'll need to do this before you install it. The headrest height adjustment (above right) is also done from the back and will need to be done before you install the seat.

While the cup holders on the Diono are sturdier than some of the competition, we still have reservations on their quality and stability.

Credit: Abriah Wofford

The Diono has dual cup holders and trays that slide out from under the seat bottom. They don't seem very sturdy and we suspect they won't last as long as the seat.

Weight and Size

The Diono is about average for weight and size, with a slight lean to the more narrow and lighter end. This booster weighs 14.3 lbs as a high-backed booster (above left). It is lighter with the back removed (above right).

This is lower than the average weight for the group and only two high-backed booster seats in this review weigh less. The width is also narrow by comparison even if it isn't that narrow. With a width of 18.4 inches, only two of the high-backed boosters are narrower. While it isn't necessarily good for carrying around or traveling, it will be somewhat easier to move from car to car and it doesn't feel as cumbersome as those with more going on or heavier weights.

Comfort

The Diono is comfortable enough, but there are more comfortable options to be found. The seat is flat and not contoured making it somewhat less cozy than other options. However, little testers thought it was soft and the headrest was good for napping. There is a stitched logo in the middle of the headrest, which nappers said was not skin-friendly on their cheeks with their heads turned to the side. The fabric is foam-backed and doesn't have much additional padding making it the least padded in the group. The fabric is rougher than most but not as bad as some of the competition.

Using the Diono as a backless option isn't as comfortable as using the back because children lose the headrest and the bottom cushion doesn't offer much padding.

Credit: Abriah Wofford

The backless booster isn't as comfortable as it is with the back in place as most of the comfortable parts are on the back. The headrest tilts in such a way that it is the best in the group for cozy napping.

The Diono quality is on par for the price, but some features don't look like they will wear well over time.

Credit: Abriah Wofford

Quality

This booster has a busy look and the fabric doesn't fit as well as it could. The design is somewhat industrial with all the fasters and structural elements exposed without covering. The seat has a firm foam pad, but there isn't much padding anywhere else. The fabric looks sofer than it feels and the mesh sides are hard to clean and we suspect they will collect a lot of gunk over time.

The shell and seat bottom of the Diono has exposed fasteners and connection points that could cause wear over time and creates a busy look to the overall fit and finish.

Credit: Abriah Wofford

The underside of the bottom is not smooth and could cause wear on your vehicle seat over time if you don't use a protective mat. While some might argue that the quality is on par with the lower price, at least one competitor scored higher for quality and costs less.

Should You Buy the Monterey XT?

The Diono did its best to keep up with the big boys and in some metrics, it rallied valiantly. However, in the end, there are better options available. It is suitable for little ones up to 120lbs and 63 inches, one of the largest limits in the group. It also has good crash test results and is fairly narrow at 18.4 inches. If the Diono were somewhat better quality or somewhat lighter, there might be a niche for this better than average booster.

What Other Booster Seat Should You Consider?

This is a budget-friendly option in a group of more expensive options. However, if budget has drawn you to the Diono, then the Evenflo Spectrum should be one to consider. This seat can go backless for a lightweight travel companion and it costs half the price of the Diono. While it has a slightly lower crash test result, it earned higher results for comfort and quality.

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