Until roughly March of '45, I'd say they performed equally well. The WAllies lesser performance relative to the Soviets was generally a function of them being more cautious, not a function of the average German in the west being a better soldier then those in the east. From March of '45 onwards, though, the German army in the west basically stopped large-scale resistance, save for a very few fanatical hold outs, while in the east they resisted to the bitter end.