Personally I'd go with Pac, he's fought the very best and made all the big fights that were there for him. Mayweather has an impressive record that could be a lot better.
pacman he's dominated 2 guys that gave pbf tough fights and when/if they fight pbf won't be pretty after the fight.
I'm not sure anymore. Pacquiao has beaten many future hall of famers but a lot of them are out of their prime.
Pacman Floyd ( like RJJ) avoided the big matches . It's not even disputed. Pac not only fights the best, he annihilates them.
It took PBF 30 minutes to stop Hatton. Pac had him to the floor after 2 minutes. And he barely scrapped by a semi retired & injured Hoya ( he might even have lost had the left rotator cuff injury not prevented Hoya to jab until the latter rds). Pac atomised both.
Pacman has MAB (past prime but still went on to achieve), Morales (past best but world class and avenged loss twice), JMM (draw and win over P4P#2, a 3 weight champ), Oscar De La Hoya (weight drained but still a huge risk on manny's part) and know Hatton a 2 weight world champ undefeated at light welter in plus 40 fights and P4P 8-10 since 2005. PBF has Corrales (very good fighter, but not as good as was then thought and not the best of chins, plus had prison issues at time), Oscar (past best but still put up a great fight), Hatton (past best weight, means nothing to me really) and Zab Judah (physically talented but put him under a bit of pressure and he goes into meltdown. Plus really a 5 round fighter who was a bulked up light welter). Thats it for Floyd. No comparison. Pacman easily.