No, all gloves are definitely not the same. I don't track miles but ones that I get good use out, fit me comfortably and rarely have issues are the cheap performance terrycloth backed gloves. I find a lot of more expensive gloves fail me at the palm at my wrist. (I both kill gloves and develop big calluses there.)

I also refuse to pay big bucks for gloves for another reason - Murphy's Law. Pay the high price, then pay again as I crash and waste them. Cheap one's? Murphy doesn't waste his time.

Ben