I put cheap JTechNow brand 5x5050 194s in my 500's dash. The smaller ones are for the indicators, which I did at a later time.
I stuck with white so as not to eliminate the colored ranges from the gauges. Also keep in mind that different colors are easier and harder on the eyes and night vision, so picking a certain color just because you like it may not be the wisest idea.
Here's my nearly-new bike with stock bulbs and white LEDs for comparison. I didn't change any of the guards or anything inside the gauges, just plugged in the new bulbs.
Here's a bad night shot, to give you some idea what it looks like when you're actually riding.
They make it look a lot more crisp and less yellowed (even though the bike only has a few hundred miles on it in the pics). I'd love to make the lighting a little more even, but for a $5, 10-minute mod, I'm happy with the results. I've had them in for over 4 years now with no issues whatsoever.