Hey, I just wanted to throw another reply on this thread. I bought the Coleman rack from Costco, very good price for a nice sturdy rack ($128 shipped iirc). But, with the stock Yakima wing bars, the rack did not line up right. Basically, if I centered the front mounts on the front bar, the rear mounts were off by 3/4". There is no way to correct this by moving the mounts to another spot on the rack either.
Since the rack came in two halves that you connect and screw together, I was able to trim the tubes down by 3/4" with a cheapo tube cutter from Home Depot. But, in doing this, I lost the screw holes that hold it together and had to drill new ones, that I put bolts through to hold things together. It took a moderate amount of work to accomplish, but in the end it works perfectly and looks good.
I just wanted to make everyone aware of this in case anyone was thinking of buying one of these.
Bart
PS - Pictures of this rack installed are on my website.