Wheels can be different in two ways (excluding durability). One is weight. Lighter wheels make a very, very small difference in climbing, especially for long and steep hills. The other is aerodynamics. Aero wheels can improve performance. For example, deep aero rims can knock off quite a few seconds on a 40 km tt, perhaps a minute or more. So, for most practical purposes, wheels don't matter at all unless you are concerned with performance climbing or gaining precious seconds in a timed event or race.