I've had a few pair of these and they are still one on my favorite shoes. I use them for warm-ups, gym endurance training, and most of my bouldering up to a certain level and type of climbing. For overhanging caves you probably want the Solution or Pythons.
For a performance fit you want 4 Sizes down from street!
There is a lot of questionable climbing shoe sizing advice on Backcountry so be careful what you use as a guide. The following suggestions (best for lower volume feet) are pretty accurate IMO and matches the words of others who seem to speak with wisdom...
3.5 or 4 down from street (Miura VS)
4.0 down from street (Cobra)
4.5 down from street (Solution)
5.0 down from street (Futura)
For example, with a 10.5 street shoe you want about a 39.5. Yes its going to hurt for awhile but otherwise they will be sloppy after breaking in.