I have a 2003 Raleigh Pro (steel) and I love it! A girl I ride with has a newer aluminum/carbon Raleigh and loves it. I don't know about their low-end bikes, but their high-end bikes are superb. One nice thing is that their name isn't as famous as others so they can't quite command the same prices for the same quality. Which is in your favor...
The Grand Sport is by no means a high-end bike, but it will be a decent intro road bike. IMO $550 is an okay but not great deal for a 2006. See if you can get a discount on other gear, like shoes, pedals, etc. if they wo'nt knock more off the price.
Be sure you get fitted. Procedures vary but they should do various body measurements to get you the right frame geometry. They might want to charge up front for the fitting, but should refund that if you buy a bike from them.
__________________
Stupidity got us into this mess - why can't it get us out?
- Will Rogers