I live in CO and have ordered parts from Rick's, Classic Industries, and D&R. I've had success with all of them and never had a problem. My experience is that Classic Ind is the best price, if you can use a coupon. Othwerwise, I tend to go with D&R, which has the same prices as Rick's and Classic, but much lower shipping and handling. Always figured that Rick's and Classic must pay 6 people to cooperatively walk down each part you order to a shipping room. I tend towards D&R these days, but they don't carry everything I need.
I know that at the place I work, S&H is a profit center. However, we sell commercial goods and the way S&H is baked into invoices and such isn't as bad ... and the people buying are doing so, often, with "other people's money." I think that I represent a fairly large customer segment -- one that is very sensitive to total price *including* S&H.
I remember a few years back when Sumitt Racing announced its new free shipping program. I was excited until I learned that they still charged a "handling" fee of around $8, which was damn near the same S&H that I typically was charged on my average order from them. Needless to say, the new free shipping program didn't increase my order rate from them. Might be a great deal if you ran a shop where you frequently ordered bulk orders of various stuff.