I've been selling APC's cabinets for quite a while now...very fond of them. "Two Thumbs Up" from me. Plus it supports a local business to me (They're in Rhode Island)
You might also want to check out Liebert. They make some really nice looking 4-post enclosed racks. They're pretty much the same as APC with better pricing. (Ie: they'll do your battery backup, have matching surge protectors mounted vertically to the rear of the rack, etc.)
It also depends on what you are going to put in them. We are curently looking at 30" wide wrightline cabinets. These are for network equipment, where we need to manage 600-700 cables. Hence the 30" width for cable management on the sides.