I have a friend with less than a thousand hours and he's an F.O. for a regional. I'd trust him without question. I've also flown with some really high time experienced captains that have scared the sh#! out of me. It really depends on the person. Having said that I like the 1500 hour requirement, but at the same time we need to continue checking, and if need be remove the weak links that are out there flying. High time, low time no matter same checkride criteria.