The overhead join can be very useful for positively identifying the runway in use, particularly at a field with multiple runways, some of which are closely angled (eg a 21 and a 25). This can avoid blushes (or far worse) consequent upon positioning for the wrong runway.
Flying a constant angle approach (which, as has been pointed out, is distinct from the overhead join, but is the useful circuit and forced landing technique employed by the military) should not make you worried about stalling, as the bank angles involved are not usually dramatic.
I've noticed on Avweb that there's seems to be some debate in US light aviation as to whether the 45 degree downwind join is or is not a good thing. I express no views on this, having no experience upon which to base any, but just mention that it's apparently one of those perennial debates.