Bike Forums - Another wheel thread

I know there have been numerous threads on wheelsets & I have used the search function. I'm just trying to get some feedback & suggestions on my specific situation.

As my sig indicates, I ride a Trek Pilot 1.2. A relatively heavy (I think around 22 lbs) relaxed geometry road bike. It has Alex aluminum AT 450 wheels. I saw some reference that said they weigh 2200 grams (altho I'm not positive this is accurate). I have about 6000 miles on the bike. Haven't really had trouble with the wheels as far as truing, but am thinking of upgrading to a better/lighter wheel. I weigh around 150lbs, don't race, but do some group rides and generally try to push the pace when I ride. Nashbar has a set of 2008 Mavic Aksiums for $180.00. They are supposed to weigh 1855 gms. If the respective weights are accurate, this is a difference of about 12.5 oz. (the Aksiums also have fewer spokes, so I assume they would be more aero).

Am I likely to be able to tell the difference; would this be a worthwhile upgrade? Any other suggestions? I'm willing to pay more than $180, but don't really want to go above $300.00. The bike just doesn't justify it. Should I just ride what I have as long as possible & save up for a better bike? TIA.

Dan