If you are thinking of the new fangled external bearing cranks they are not that much better than ISIS to be honest in reliability. Square taper is still the most reliable system but your choices are limited these days. Another option is to look at SKF ISIS drive bbs. I have been known to mash up an ISIS drive bottom bracket in less than 6 weeks. I have had my SKF for nearly a year and a half and it has just started to develop play.
A truvative gigapipe on a 'Dale I was given to test a couple of years ago developed play after 4 weeks
For the last year been using shimano external and they're still running smooth and play free. Not had one creak out of them. Maybe their lifespan is a lottery but, imo, I think it's more likely down to how much preload is used when they're installed.