We used Happy Limo in January, 2006 and were very pleased with their service. We paid for a town car, but for the pick-up they sent an Explorer (don't remember if it was a limo, buit the kids loved it). We also used the grocery stop which was wonderful with two little kids addicted to milk.
I would use them again. I remember getting a discount of about $10.00 off also,maybe from mousesavers.com?