Hiya Charlie!
Welcome to planDisney! Man, I miss my kids in stroller days. My youngest is 6 and I'm still thinking if I should bring one with me to the Parks or
rent a stroller. Sometimes the Park days can be so long and tiring for their little legs and I appreciate the cupholders for all the drinks we have to carry!
According to
Park Guidelines, strollers larger than 31" (79cm) in width and 52" (132 cm) in length are not permitted. Stroller wagons are also not permitted. I confirmed the sizing on the UPPAbaby website as easily fitting into these measurements even with the toddler seat attached. Now, I don't know exactly what model you have but please confirm the sizing and see how it fits with what I gave you.
You will love having your stroller with you in the Parks. A stroller tip that I would like to share is to make sure you make your stroller noticeable and hard to miss. An UPPAbaby Vista Stroller is not cheap so I would make sure to label it and make it clear that it is yours. I like to attach ribbons on the handlebars but maybe you can make a cute sign. Another tip I suggest is that at night these strollers can become impossible to find in the sea of stroller parking so I use glow sticks or battery-powered fairy lights to make my stroller stand out. It also makes it more magical for the kids. Don't forget a stroller fan! My kids did so much better with a fan or fan combined with a mister to stay cool on those long hot Florida days. Any fun distraction to keep the kids happy is key for everyone to have a great day.
I hope this helps and that you have a magical time!
Let me know if you have any more questions as I love to enjoy Walt Disney World with my little ones.
-Nimmy