I had the Rev Model X in 17x7 and took them off because they would bend and crack too easliy in moderately bad potholes. The lip is too soft, and bends with 40s on the rim if you hit a pothole that's more than an inch or two deep. Then once it's out of round, the wheel vibrates until the closest spoke cracks to relieve the stress.
I got them here:
Link
But they seem to have taken down their online store. They may still ship. Call up and see what they have in stock. I think the guy I talked to was called Mark. They may also be able to point you at some higher quality rims that would be stronger.
Maybe I would have had better luck with 45s, but i doubt it. Two rims in three months is not a coincidence, especially in the summer and fall before potholes get deep from frost damage.
I put a set of 16" stock E1 rims and am going to get some real forged rims instead. Either that or move up to OZs. At least they have a reputation of being stronger.