Hope this helps. . .
First, it is my Wife, 9-yr. old Daughter and I. We all have quads and just in the last year bought a mini-rail (Tom Pro).
Our first trailer was a FT2200 (basically a Front Sleeper 2600 except a tent in front instead of a bedroom.
We knew we were looking at a Mini-Rail so, we went to the LE3505 + 4' (LE3905).
We absolutely LOVE it.
The bathroom is basically the same. The sky-light in the shower is nice for me (6'2") as I can actually stand-up! But, I am not in the bathroom that much to care about how big it is. As long as I can take care of my business and take a shower I'm fine. I figure I'm in the shower for about 30 minutes over a one-week trip so, who cares if it is tight. That's just me though.
As for pulling, there is no sway! The only times (2) that I've felt something were when I was in the valley and it was an extremely windy day. I could feel it that day. Also, last year on our way back from Glamis, when we came over the Grapevine we got into a little tunnel on the N. side of the Mt. where there is a lot of wind. I slowed down a little for about 5-miles and it cleared up after that.
Last trip over Donner pass on the way back from Sand Mt. my buddy who was following me in his tag FS3600 with stabilizer and load dist. hitch called and said he got blown around pretty good at the top of the summit. . . I asked, "was there wind?" Seriously, I didn't feel a thing.
This thing tracks awesome also.
Someone posted something about the total length of the FSW3200 (I think) and it was like 34'xx" or something. I was thinking, MAN, that's not much different from the LE3905 when you are hooked up!
If you go tag for that length, I'ld definitely look into a serious hitch but, in the long run I really believe you'll be much happier with a 5er.