Los Angeles, California
If you can afford it, PLEASE get the front of line pass.
Best seats in the house and you can repeat your favourite rides with virtually no waiting time, eg The Mummy 6 times in 20 minutes (this was in Nov 2011).
Las Vegas, Nevada
If you're like me, this was well worth the money ie. to be chauffered around everywhere in comfort and be well looked after.
Advantage over the bus tour - more flexibility : we got to spend quite a lot of time at the Hoover dam, you also avoid long queues because the excellent tour guide will get you to the Helicopter rides before the bus tours arrive (Thanks Ken!)
I would definitely choose Pink Jeeps if I decide to do this again.
Well done to Viator too, booked everything online in the UK and everything went according to plan.
Very very impressed.