The Petzl Corax is a great multi-use harness, especially for those who are either just getting into the sport of rock climbing, or those who want one harness that can do any job pretty well.
The Corax has all of the features of a great cragging harness: light weight, durable, and simple. It has two gear loops on each side, as well as an extra small loop on each side, which can be used to rack ice screws in the winter. All of the buckles (two on the waist and one on each leg) are double-buckled and therefore just need to be tightened in order to be used properly. The waist and leg loops have enough padding to endure some hanging, but you may want to search for something more comfortable if you’ll be on a larger wall with consistent hanging belays.
What makes the Corax a great multi-use harness is how much it is able to adjust. The most notable feature of the Corax is that it has two adjustment points at the waist, which make it easy to always fit your belay loop centered, no matter how many layers you have on. The leg loops adjust to be big enough to use with mountaineering or ski boots, and the leg loops detach from the back so you can wear the harness on a bivy ledge or when nature calls.
While there are more specialized harnesses out there for the different disciplines of mountaineering, the Corax is able to excel at rock climbing, while doing a pretty good job at everything else.