You have a few years on me, but not many. I may be about to help you with your decision.
I'm 53 and have been riding since I was 10 (street & motorcross). Currently I own a '05 FJR1300/ABS and a '05 Busa. But make no mistake about it, there's a world of difference between these two bikes. The FJR has plenty of torque, claimed 145hp, is fairly quick, and has nice handling characteristics (not sport-bike handling, but very comfortable handling). Acceleration and corning; a FJR will smoke a Wing with no problem at all. The FJR is approximately 60% the weight of a Wing. Triple digits appear fairly quick. You'll think you're doing 65, and look down and find yourself in the low triple digits. Even under full throttle I rarely worry about the front wheel lifting, although it's possible if you really want it to.
On the other hand the Busa seems to have endless power. More power than most people will ever fully use. Few riders push their Busa's to the absolute limit (although some of the really brave do). Nail the throttle and you'll be kissing the tank, even at typical highway speeds. The Busa's acceleration curve is wide (from idle up) and awesome. With just occasional riding I got used to the power on the FJR in a few weeks. After nearly a year I'm still no where near comfortable with full throttle acceleration on the Busa. It's torque just seems to never end!
My suggestion is try to find a used Busa and FJR and put some miles on both of them. You can push the FJR hard into the turns and have a lot of fun with it. Then again the FJR doesn't have the crazy thrill factor that the Busa has. The FJR has a hands down better seating position than the Busa (at least for me), especially on longer trips. But I find I'm getting used to the riding position of the Busa, the more I ride it.
Here's my comparison between the two stock bikes:
Scale 1 to 10 (10 highest):
Busa FJR
Power 10 7-8
Torque 10 8
Acceleration Rush 10 8
Handling 9 8
Over 50 Comfort 6 9
WOT Fear Factor 10 7
If you find yourself leaning towards purchasing a FJR, PM me. I may be interested in selling mine. (Low miles, perfect condition, and $2K worth of extras). Good luck with your decision.