D2S Morimoto XB Hid are best for price and quality imo. I tried DD but did not work at all and I have the 2010 g37x coupe model.

 

Last year I tried these:

Maxlux 6k HIDs - I liked the color it had that white/hint of blue "diamond" color. Unfortunately one of them would sometimes not fire up, I swapped the bulbs (sides) and the problem persisted. Eventually they both started flickering so I returned them.



I ended up with these:

Sylvania SilverStar 5k HIDs - The color on these was superior to stock more white but didn't really have that "diamond" hint of blue look. I actually thought light output increased when viewed side by side 4300 vs 5000k - not quite sure why. These bulbs however have been solid for over a year now (15 months).