Printing the cards yourself, even if you do quality artwork - always looks a bit amateurish. It says "I'm not here to stay" in peoples minds.
I've recently had some printed at this site -
http://www.printcarrier.com/gb/You do your own artwork and upload it.
I used to be a printer for 18yrs before I went window cleaning, and I would say the quality is great especially if you keep the dpi above 600 and go for the 300gsm card.
The price is amazing for full colour @ £31.00 for 500.
The key is to get your design looking good and professional from the start.
Keep it clean, classy and clear. Avoid comical logos or cartoony pictures. IMHO.