Mods don't equal problems. What I've done, in order:
Glasspacks - Great sound, controversial looks and concept...
CycleCat Tall Bars - Much improved comfort, gorgeous parts.
BrakeTech Floating Iron rear rotor and Ferodo Platinum Pads - Eliminated the squealing/howling, and it actually slows the bike down some.
DynoJet PC III - Runs better, and I can eventually (soon) dyno-tune to make it run even better, and compensate for any engine mods in the future.
Yoyodyne Clutch Slave - Easier clutch pull, wider engagement zone, prettier than the stock unit.
Yuasa YT12B-BS Battery - Replaced the leaking stocker.
PvL Oil Temp Gauge - Looks cool, gives me some idea of oil temp.
S4R Mirrors - Look better than the stock mirrors (not hard), and work a little better.
Problems I've had or am still having:
Leaking Vertical Cylinder Base Gasket
Leaking Stock Battery
"Lost The Handle" on Front Fork Adjustment
Tires Worn Out ;D
None of the mods have caused any problems, and in fact have eliminated some potential problems, and fixed others.
Go for it!