Hello, this is my first post. I love this site!

I've had an Allez 24 since last August and put about 1000 miles on it so far.
http://www.specialized.com/SBCBkMode...c0aerft.j27004

I love the bike for the price. It seems to me that the best upgrade to invest in is a good set of wheels, but I don't have a whole lot to spend. I am looking at Mavics offerings.
http://www.mavic.com/servlet/srt/mavic/road-prod?lg=uk

I am confused about machined vs. hand-built wheels. For example, what are the pros/cons of a Cosmos wheelset vs. a Open Pro/Ultegra wheelset? What wheels would be worth putting on this bike? Any comments on the Alex wheels that I am currently riding?

Thanks,
Russ