I've a XB12R and a F4i. I've a pretty long comparo in SBR site. Very easy to search. Anyway, here is my long"er" term update - in comparison to the Buell, the F4i is almost boring to ride.
Initially you would find the Buell un-refined. But the longer you own the thing, the more you will like it. The chassis is wonderful. Robust is the word that comes to mind. The ideas / designs that puts into the chassis is amazing. You will NOT be able to tell the difference from the bike with a full tank of gas and an empty tank at all. BTW, the MPG is at mid to high 40's for commuting.
Maintanence on the bike is very easy (in comparison) as well. Mechanically, it is as reliable if not more reliable as any thing else that's out there. The bike does eat up tires quicker, though. About 20 to 25% quicker comparing to my other bike. This is due to its short wheel base.
How it rides.... Well once you get your bike dial in ( and let me emphasis, dialing it in takes much more time than other bikes) it is stable as a stone wall. The window is very narrow in terms of suspension setting for particular weight of the rider and you will have to get the bike right-on in terms of the settings. But when you have the suspension set up correctly, boy, mid corner, exist is just so stable is unreal. Mid turn correction is easier (in comparison) as well. Mind you, I've had the F4i's suspension reworked by Phil at Aftershock. Now keep in mind, when you test ride the bike, most likely the suspension would not be set to 100% to you ideally. You might even think it is a piece of crap due to that. When I first test rode the bike, boy, I was thinking, what a piece of garbage, it wouldn't want to turn at all! But l gave it another chance when someone from BARF pointed out that the suspension setting has everything to do with it.
You'd think the Buell with it very short wheel base is difficult as heck to ride in a straight line (i.e. on highway during commute); on the contrary, it is as stable as the F4i when hitting bumps/ cracks (like those on 101s by Mountain View/85 area!!) Also, as far as weight of the bike is concerned, well, I think it is like 30 or 40 lbs heavier than my Honda, but you DEFINITELY don't feel the extra weight in comparision.
Brake performance - with its's single sided brake rotor, you do feel that you have to use about 15% to 20% more effort (comparing to my F4i with steel lines) in terms of lever squeeze. But that's no big deal at all to me. The brake is as linear/predictable as anything out there.
Engine - if you want to ride this bike like an i-4, and are expecting that kind of engine behavior, well, you should not be looking into the XB. It behavior very differently and it is very additive. The torque is definitely there but if you are comparing this XB-9 (~985cc(?)) to any other liter bike in terms of acceleration, well, any later model liter bike will eat the XB-9 for breakfast.
On to style - it is definitely one unique bike for sure. None of this boy-ricer style in its design. The attention you get from people are sometimes funny. There are couple of times where when I was slowly pulling into my self-proclaim parking spot at work (under a roof of a building where not officially a parking space), some people just followed my bike and try to figured out what the heck type of bike it is. Numerous times when I'm fueling up, I would turn around to hang the nozzle back and catch people just standing 3 ft from the bike staring at it. Their car / truck would be somewhere in the next aisle 20 ft away.
Now onto the negatives; just like everything in the world, there are negatives to this bike - first and for most, the lighting on the XB-R's. The lights (the projectors) aren't above average in terms of performance to begin with. I've even been reading on the Buell XB board that the reflective paint will degrade over time. Those people in Europe doesn't know how to make good headlights I guess. Yes, the headlights are from Europe (Brake & suspension from Japan, Chassis from Germany(?), couple of other things from Europe / Japan and engine from USA... BTW, some might say that the engine is just the Sportster's engine - that's is not true and I don't have time to go into that). In the XB-S, the lights, I believe is either-or. This means one side is low beam, and one side is hi. You can't have both lights on at the same time. You do, for both S & R, have a passing light trigger (like the one on Suzuki's SV's).
I will supply more later since I can't remeber anymore at this point.
