The 35 is an older model and is more similar in size to the 380.
The 350 is a newer model is more similar to the 32.
The 35 uses the same galley as the IP40
The 350 uses a smaller galley, 2 burner stove but a better ice box.
The 35 has traditional bunks, V and Qtr
The 350 has island bed forward and sideways bed aft
The 35 costs less than most 350
The 35 has full engine access with the engine at floor level
The 350 has the engine lower and under the Qtr berth and more aft
The bow is higher on the 35 and the sheer line is more pronounces
The sheer line was removed on the 350 and most IPs w/XX0 making the bow lower and the cabin top higher
For me, I prefer the older IPs due to this lost sheer line.
I do like the lower engines for quiet and less sound, but thats it.
I do like the newer ice boxes of the 350
The island beds are nice at anchor but would not work as well under sail
It really is a toss up. You need to get onto each boat and feel the space and the set up. Then once you feel the space next is the budget. Most of us will buy the most boat our budget can take.
Enjoy the shopping, it is a fun time...
Hayden