Either the ultrafires are running poor drivers or poor LEDs... or both. Impossible to tell if your LEDs are Q5s looking at them ... until you compare with another Q5.
Putting a p3/p4 in saves a few dollars(significant in a 21$ light with free shipping) and its still an impressive light. I gave up ordering LEDs from these guys because you don't know what you're getting.
I have a bunch of cheap flashlights from DX and Kai. They are all mediocre quality (though I do like the single aaa buckle lights from Kai they are ok build and take up no room in the seatbag).
Regarding colour... On my helmet I switched from a minewtx2(very white) to a more yellow DIY (exact same colour as my bar lights) and it was a big improvement. The bar/helmet lights blend perfectly.