i just bought and laced a couple of them 2 weeks ago: a wm3 for the front and wm4 for the rear.
first off, they had dramatically different extruded section shapes between the two, with one of the channels being much deeper and wider than the other. for aesthetics, i would order the same width if at all possible.
secondly, the front rim had a pretty bad hop in it at the welded seam. it was about .065" hop in the bead of the rim, in about a 2-3" section circumferentially. pretty bad. the hop was slightly less bad at the seat of the tire, where it really matters, but the bead was not great. it ended up building up ok, but the spoke tensions were a bit disparate. we'll see how it ages.
the rear rim built up great. even tension, very true, very round, with all the holes drilled in the right spots in the dimples.
buchanan's has great service and stand behind their products, but the front rim was not fantastic. they don't make them, so i can't hold them responsible for the manufacture of the rim. i've had great luck with their sun rims, or the excel rims. the excels come in a shouldered version as well.