For anyone contemplating HID kits, I recently had the chance to install the retro-solutions econo kit on a friend's mini cooper. I run the upgraded 55w version, he had the 35w base version. Both kits were ordered with capped bulbs which I highly recommend, although on a vehicle like the cooper there is a huge plastic bulb shield so capping isn't necessary. If choosing between the two, I would go with the 55w premium version. It's brighter, for H13 bulbs you get HID with highbeams, the 35w kit has a separate standard H1 bulb so there is color mismatch. The ballasts are better on the 55w kit, bulbs get warmed up faster, there was a slightly jitter with one of the ballasts(35w) that went away after warm up.