Do you really get that much difference out of different levers I thought about switching but I wasn't sure how much of a difference I would feel
They are a personal preference, like a seat.
Different styles feel different in your hands, angle, adjustment, shape.
Long or short levers are available also.
Myself and many people like the short levers, but you never know until you try them.
I have Pazzo knock-offs that I've had for 2 years with zero issues.
They are an improvement for me as they fit my hand/grip position better than stock. As well are adjusted to the where they engage far away from the bars(you can adjust them engaging close to the bars or in between, up to you).
That makes it easier for me to use one or two fingers on the brake or clutch without crushing my other fingers that are holding on.
ASV levers(will be on my busa eventually) have the finest adjustement of aftermarket levers and a great warranty.
Basically you just need to try a quality brand like Pazzo, ASV, or a few others. Decide which you like the look of, and what length. You may get lucky and get a pair you like. If not, levers are an easy sell(or return) and you could try another.
Technicaly levers aren't a performance gain.
However, if you find a pair more comfortable than stock to you personally, then you are more comfortable and in control.
It's kinda like shoes, if they feel right to you, regardless if they fit
