You know this really kills me...if you go on the 700 forums and have people ask these questions, none of you even take into consideration that the 700 may not be the best choice, but you all jump at the chance to say "GET THE 700 IS THE BEST THING SINCE SLICED CHEESE" but you come on here suggesting anything but almost...the 350 isnt in the best thing but there is absolutely nothing wrong with it....i may be being bias as i own a 350 but at the dirt cheap price and the fact that in the trails it keeps up with any 400 stock and you can almost do the big 3 for under 300 bucks is a nice selling point and with the big 3 and a 12 tooth front sprocket i would bet it would be most 400 in a drag and you would still have some money in your pocket...granted you bought a newer 400ex...yea you could get a 95 for way less but its a 95...
For the OP I went from bikes to quads just like your saying you did and there isn't anything i would rather have right now.
Dont get me wrong, I love the 350, I have one, my wife uses it. Iam 33 years old now. I will still get the 3 mods for her, after I have upgraded the suspension. The 350 is a great bike, but in time you will have to get better a-arms as well as new shocks, plus the big 3.
For my height and weight, it is not all that comfortable, but the 700 is.
The stock 700 is an excellent machine, you can get one 2nd hand for quite cheap, and you do not have to do any mods to it, keep it like it is, and enjoy for ever more and many years to come.
What I am saying is, coming from the Yamaha XT 500, I really enjoyed that high torque from low revs all the way through, so the 700 was easy to adjust to riding wise, compression braking, etc.
I still enjoy riding the 350 very much. Just that if it was my only quad, I would have always wondered what the 700 would be like. Now I enjoy the best of both worlds!
The 350 however has some factory flaws:
#1: Positve camber on front wheels which cannot be adjusted
#2: Hard to find neutral when hot
#3: Struggle to engage forward out of reverse
The 700 does not have any flaws that I know of.