I have 4 Morimoto 3Five HID ballasts for sale. These are by far, without a doubt the best aftermarket ballasts available anywhere.
1) Morimoto has a much quicker warm up time, as quick as some OEM ballasts
2) Better noise control: You can't hear them "singing" like the cheezy eBay ballasts
3) Electrically shielded output cables (so you don't hear the ballasts/HIDs working through your stereo speakers
4) Fully potted electronic boards - the electronics inside are encapsulated in a thermally conductive epoxy to make them absolutely waterproof.
5) 2 year warranty against manufacturers defects
6) Compact size, igniter included in ballast housing - better design (like OEMs)
7) Output of these is 35 watts, not the INPUT. Normally manufacturers of ballasts rate them at the input (power usage) but you don't get 35 watts output, typically outputs are 26-31W) - I've measured these at a minimum output of 35W-37. So your lights are brighter, and more vivid looking.
I am asking $40 per ballast, plus 5$ shipping per order (48 states only - so buying 2 of these would cost you 85$ shipped total.