I had bad luck w/ my previous pair of alex rims but just went w/ the LHT ones, no budget room for new wheels for me, and have been very (*very*) happy w/ the stock ones, 36 spokes 26". Bombproof so far, and I've taken some big loaded hits (one pothole inside a puddle in particular).
I didn't buy mine complete but my LBS recommended the Salsa Delgado's for me since I'm a bigger guy and when I have it loaded I wanted something bombproof. Just go them built last week and so far so good!
I built up my 54 cm LHT with Velocity Aeroheat 26" rims, 36 spokes, DT Competition 2.0/1.8 spokes, Shimano XT hub with Continental Travel Contact 26" x 1.75 tires. Initially had flats every 50-100 miles because the Aeroheats use spoke hole plugs instead of rim tape to protect the tube (supposedly to save weight) and there were rough spots on the rim. Fixed that by putting in rim tape. Other than that everything is very satisfactory.