there are alot of choices you can make...
vapors...
vepors...
acewells...
r6's...
or even bicycle speedos...
pretty much your pocket book and personal preferance...
******************************edit... found another old post of mine that shows more detail***********************************
There are Veypors
And then Vapors
Here are a few other digital gauges you might consider:
Acewell

Dakota digital (made for cruiser bikes, but can be converted to high rpm bikes)





Motogadget (Sleek and pricey also)
Wire Plus (another cruiser based gauge)

Digital Mirros by Custom Cycle (another cuiser based one but yet more exotic)


And lastly for those of you that have "very" deep pockets...
Yes, Intel will make you a computer/gauge/gps/you name it for your bike:


This is all that I could find of gauges. I do know that people use bicycle gauges too. That is what I first bought was a schwin top of the line gauge, till I found trail tech.
Anyhow, be the judge yourself and just click the pictures as I have them linked to each site.