Let me offer what I see as the gain from the lighter wheels. On rolling hills you will certainly be able to attack them harder yet still feel fresher. Effort on long climbs will seem easier but yes may not be any faster. For me it comes down to things feeling easier on the climbs and not being as wore out after the long climbs. When things get really steep and you lose concentration it will be easier to get back up to cadence. Plus the obvious benefit of what will probably be a better built wheel. I've bought two light weight sets in the price range you mention. Williams System 30s and then an even lighter set of Zen Cycle wheels.

I ride solo and consider a ride of 40 or so miles where I can maintain a 20 mph average to be really good. Maybe if I was faster, did group rides, or less climbing aero may matter more but for me I prefer the lighter weight and consider it money well spent.

Oh, and you like the look of clean, plain wheels Zen did not put any decals on the set I got from him.