^ great question, what oil are you using???? Ha!
I have McColluch HID's in both High and Low. From the research I did, most people feel that the Low beam is enough light that you will not need the high beam. I can tell you from doing some 20 mile stretches in the back country, I liked having both High and Low beams HIDs. But like previously mentioned, the High beam takes a little while to come up to brightness, it is useless to flash to pass or (on coming vehicles who think you have your high beam on all the time, thus blinding an oncoming vehicle coming in your direction). So basically it's up to you. I also went with the lower temperature lamps so it's closer to "white" light vs. the blue/purple...
As far as starting issues... the only thing I know that's related to the starting issues is that the HIDs don't like the starting cycle (low voltage) and may cause them to act funny (maybe others can describe it since i have never), so when I installed mine I opted to put in a time delay relay. DEI 538T or something like that, I'm sure there are plenty of threads discussing that topic.
Regardless, you will like it and don't forget you may need to adjust your lights (on coming cars may not)