3 people before me here said to get the slide out. I hope the few who got the 2552 without the slide out, will reply in with their thoughts about their decision.
No doubt about it, the slide out is most popular. But my personal thoughts are......If you are NOT traveling with large pets, or are not seriously over-weight people who needs lots of elbow room, the No-Slide with over-size dinette just might be your better choice.
You mentioned the desire for lots of extra storage. The No-Slide dinette will provide piles more storage than the couch inside the slide out. The bench seats offer lots of storage, even more if you request Phoenix leave out the drawers so you can utilize the entire cabinet from above as well as the side door. Also the hanging cabinet above the dinette is deeper, wider, and taller than the one inside the slide out.
CLICK HERE to see our 2350 with a no-slide dinette. The 2552 version can be made even bigger offering a bigger table and additional leg room.
There is a long list of mostly pip-squeek reasons why a slide-out is not the better choice, but only two big ones why it is.
1) more spacious interior when the slide out is open
2) better resale value because most people prefer the more spacious interior.