Hi,
I was in VilaMoura last september, and it was choc-a-clock with gangs of irish and english lads. It seems they were mostly over for golfing holidays.
The marina area in VilaMoura is filled with bars advertising giant TV screens and rugby/football matches, and beer promotions. I hated it, but it might be good for a group of lads. (there were no groups of girls though, if that matters!).