2euce I have a racing 6 speed at the house and I wont be putting it in the new bike.
There are 2 concerns with them that you should be aware of.
1st if you buy the standard 6 speed the 1st gear is too tall so if you get on it and shift into 2nd and dont stay on it its like you down shifted.
Concern number 2 if you get the full out race gearing in it when you hit 6th gear you will feel like your lugging the bike.
A few posts ago I was asked why i had the 21 tooth gear on the engine instead of the stock 25 tooth gear. This was because you need a 113 inch motor or larger to drive the racing 6 speed. If you only have a 103 or 107 you need to change the gearing so that you can take advantage of the tall 1st and 2nd gearing as well as make the 6th gear useful to you. After spending all the money I did on the transmission I feel I would have been better off long run in not having bought it at all for a touring / playing application.
Also remember 3rd and 4th gear are relatively the same as what you have now.
The big difference will be that the shifting is a lot better in the way the gears mesh. Another thing to be aware of is there is no hard lock on 1st gear by that I mean you feel like you can continue to downshift even when your already in first gear ... today you step on the shift lever and it finally bottoms out when your in first gear the baker will not do that. Can make for an interesting find of neutral at times

Maybe more info then you wanted,
-Unbalanced