We can find the key specs and features of Diono Monterey 4DXT and Monterey XT in the table of similarities and differences below. It’s important for us to look at their specs and features before we can talk more about their key differences.

In addition to the stated limits, there are some physical limits that come into play with booster seats. On the small end, we found that our younger child didn’t get a good fit in her other Diono booster seat until she was around 43″ since she’s more legs than torso. Fortunately the 5iST gets a lot smaller! I think she would have been just fine around 40″ since the lowest belt guide height I measured is 13.5″. You can see here how the 5iST compares to its cousin the Diono Monterey 4DXT in their smallest sizes. The Monterey XT’s lower anchors are not required and can only be used in vehicles where the lower anchors align directly behind the connectors on the Monterey XT. You shouldn’t use the lower anchor connectors on a booster in a vehicle seating position with offset anchors, as the booster won’t be positioned correctly for the seat belt to fit properly. Honouring the first collaboration between Diono and Berlin based design studio, WhiteID, Monterey® 5iST FixSafe™ combined our signature world-class American engineering with forward-thinking, edgy European design to create the next generation of child car seat. Monterey® 5iST FixSafe™ continued to turn heads across Europe, catching the attention of industry experts and innovators of the technology of tomorrow.

If you’re considering the Diono Monterey 5iST for kids near the upper end of the size range, you won’t be disappointed! The side wings automatically widen as you raise the head rest, giving lots of room for growing shoulders. Diono boosters are deservedly known as great options for broad kids and this one is no exception. These lower anchor connectors are attached to the seat differently from those that are used for installation on harnessed car seats. They look like they are upside down and it will feel strange to install them this way, but it is correct. Easy-adjust - 11-position headrest that grows up with your child. Engineered for safety and comfort with 2 layers of SafePlus® Side Impact Protection. Not only does the headrest adjust but the seat has a 6″ deep sidewall expansion. Simply turn the dial at the rear of the car seat to expand or reduce the sidewalls. This is a fantastic feature and will accommodate children who have wider frames and will also be good for when children wear extra layers in the winter. I love how versatile this car booster seat is. It could be used for any child who needs a Group 2 or 3 car booster seat and can be adapted to suit a different child within a few minutes.

The diono Monterey XT Fix Booster Car Seat is a forward-facing Group 2 and Group 3 car seat which means it is suitable for children who weigh between 15 – 36kg (generally aged between 3 and 12 years old and up to a maximum height of 150cm tall). Flexible features I have to say that from a subjective perspective I’m really impressed with the Monterey 5iST, and my kids are as well. Nothing is perfect so here’s my personal list of Diono Monterey 5iST advantages and disadvantages: Diono Monterey 5iST advantages Engineered with our most side impact protection - our rigid shell is reinforced with 8 layers of high-impact aluminum and EPS energy absorbing foam, to protect the head, shoulders, and torso.

This time, Design Center for the Baden-Württemberg International Design Award Focus Open awarded Monterey® 5iST FixSafe™ winner of the Gold Focus Open 2021. These are both great booster seats and they work as different tools in our family’s toolbox. Diono Monterey 5iST vs Baby Trend PROtect 2-in-1 Fortunately the Diono Monterey 5iST should fit in the overhead bin on many planes (at least in the US and Canada). The folded size is 17″ x 8″ x 23.5″. As you can see, it’s about the same size as my carry-on suitcase so it should go in the proper way.

The other folding booster seat in our family’s fleet is the the hifold by mifold. You can read my full hifold review for tons of info. While the Monterey 5iST FixSafe is about making a traditional booster seat more compact and somewhat more travel-worthy, the hifold puts the travel aspect first.Your child will always have a comfortable, secure fit with the Diono Monterey XT, thanks to its 11-position headrest and a width that can be adjusted up to 20 inches. It boasts expandable side wings and two recline positions. This makes it easy to dial in a precise, proper fit whenever your child grows, and also makes this model is a good choice for children with larger builds, who might find many other car seats too uncomfortable and restrictive. Diono won prestigious iF DESIGN AWARDS in product design for the Monterey® 5iST FixSafe™ chosen by the 98-member jury, made up of independent experts from all over the world in 2021 and 2022. The Monterey XT is a well-fitting option for any child who is ready to ride in a booster seat, especially those with larger builds and those who prefer some extra padding. The Monterey XT is easy to install and use. The lower anchor connectors, cup holders, and adjustable width make the Monterey XT uniquely customizable to fit a wide variety of passengers. While it is bulky and won’t work well in a three across situation, the Diono Monterey XT is a great option for bigger littles and littles who prefer extra padding. Will it actually fit a kid who is my height and 120lbs? At that point it’ll depend a lot on body structure, but rest assured it does get very, very wide. As with all boosters, you need to make sure that their ears are fully contained within the booster seat. While the Monterey 5iST is going to work for nearly kids until they are done with boosters, the Baby Trend tops out at 100lbs and 57″– fine for some kids in some seating positions but not universal. One nifty aspect of the Baby Trend is the super flexible positioning for the seatbelt: the shoulder belt can go either over or under the arm rest depending on what gives a better fit and the shoulder belt guide can be in one of three positions.