ETA: There is a new kid in town!
My 370 frame now wears a 370 PRO mat and I really like it!
Now it is an even a harder decision whether to spend the extra cash for a 550 PRO because I believe a 350 Pro would have satisfied me. The extra couple of inches are nice but not necessary if money is tight. The extra 6 cords come with a differently designed mat making it feel larger. The 370 petals are smaller and quieter too but I know I like my 550 skirt mat so do not think the petal mat is worth the extra bucks.
Bottomline, if you want a fast firm bounce and money is tight, get the 350 Pro.
(Note: Plantar Fasciitis feels better with a firmer mat)
ETA: I really like the PROBounce 48 inch model which is now $350 (pre-order was just $250). The Bellicon starts at $700 for 49 inches and no longer charges extra for shipping. There is no 48 inch Jumpsport and their 44 inch 550 no longer has a discount through Costco so is ~$500.