American Classic 420 - opinions and alternatives

I am getting a PowerTap SL 2.4 powermeter, and must decide on what wheel.
Currently ride cervelo team with dura ace and velomax/easton circuit wheelset.
The Easton Circuit wheelset weighs 1650 g (3.6 lbs). I weigh 65 kg (143 lbs)and ride both flat tempo and in the alps. I prefer a stiff (uncomfortable) setup. I would like the new wheel to be an upgrade:
1) not add weight to the bike
2) same or better aerodynamics/hub resistance,
3) same or more stiff, reasonably durable.

Some options:
1) One LBS option is American Classic 420. I've found complaints on the web about these dating to before 2005. Any more recent opinions?
Apparently, an AC 420 wheelset with powertap would be about same weight as my current wheelset.
- Will it be equally good (aerodynamics/hub resitsnce, stiffness and durability)?
- The American Classic front hub is 58 g. (2 oz) - i.e. half the weight of most other - is it still OK?
- Should I get 18 or 24 spokes for front wheel?

2) Mavic Open Pro seems to be default with powertap. How does this compare to the Easton Circuit and to the AC420? (weight, aero and stiffness) ?

3) Do you have other recommendations? (I am not willing to go to the price range of e.g. Zipp wheels)

Thanks a lot
Henrik

I had a set of American Classic 420s, with Sapim CX-ray spokes. I'm a little on the "weighty" side - 185lbs but have had no problems with them, even descending on the rough side roads at speed.

Some people complain that they're a little on the flexy side but they work pretty good for me. I haven't suffered any weirdness either on high speed descents like Monitor or Sonora passes where 60mph speeds combined with crosswinds are common.

Powertap hub, 28h, laced to a Velocity Aerohead OC rim. 14/15 spokes 3cross, headout or inside pulling, brass nipps.