Though I haven't ridden a GT200i, I did sit on one. And for me, the seat on it is more comfortable (and a little lower) than on the S 250.
Now, I wish that I would have bought one instead of my S 250 though it is my understanding that the S 250 is a little faster and that's what I was looking for at the time. Also, in my case, the S 250 that I bought was sold to me as new (zero miles & a 2 yr warranty) and a huge discount in price.
The dealer would not discount the 200i or I would have bought it. And old geezer is right, the 200i has less underseat storage but it has a small glove box and it comes standard with a top case.
The maintenance intervals are longer on the 200i and fuel injection is nice to have.
If I had it to do over again, I would buy the 200i.