I have both Hella 500 & 700's (have 500's on my 2 door Montero and 700's on my 4 door) with the stock 55w bulbs. Over the years, I've come to realize though that I rarely need their reach off road because the reality is, I'm driving no faster than 45mph on the trail at night. Yes, it is cool to be able to really reach out and light up a mile ahead of me but in all practicality, I don't need the light out that far.
If I were to buy lights today I'd be focused on buying decent fog/flood lamps instead and that being said, I'm not sure how much brighter they would be with HID's.
So what kind of night driving do you intend to do?
Other than that, it does sound like a decent deal so long as the light electronics are solid (even if they provide a lifetime warranty).