I went from stock- to 200, to 280, to 300.
Keep in mind everyone uses different brands which have a little difference in crowns, compounds etc. Not to mention wheel widths. Plus changing from different wheels with different weights.
When I went to a 280, everyone said it was the worst handling (that was with the Metz) most said the 300 Avon was better. I went to a 300 Metz- a little lower tire than the Avon.
Can't say I could tell a diffrence in the 280-300.
Best handling was a 200.
Biggest thing is where I live here in Michigan- I made all my changes in the winter (where we might be off the bike for 6 months) after this period of time, the bike itself feels new, so when you put a new tire on or change the handle bars etc. - it all feels new and different. But, you get used to it all in just a few miles so it's not like putting 20,000 miles on in the summer and switching from a 200 to a 300 in July- know what I mean?
I am certain you will lose time going down the drag strip (or gain time I mean!) In the dyno shootouts tho- with the 280, I consistently put down numbers in the 160's (8#'s boost) and with the 300 I did a 185.something at 10#'s.
My 280 had a horrible flat spot that made handling bad- but, this was after way too many burnouts.
There is a difference going to that big a tire- I just don't really notice it after you have been on it for a few minutes. Going to a stock bike feels so different to me but, the seats, supension, bars, pegs- everything has been changed on my bike to fit me- so when someone else gets on my bike they feel ALL those changes, not just the tire. The only one who said they "felt" the big tire on it was a Fat Boy rider and the V to that bike are pretty different.
If you are a very aggresive rider- fat tires are going to give up a little handling.
If you are like me, lot of cruising, jump on it when it feels good, not too many winding roads here, the fat tire looks really good, didn't change anything or the way I ride.
I have seen guys with the fat tires out ride guys with skinny tires- only difference there is the rider.