I use 45,65,85,105,125 stainless rounds.
I have at least five basses strung with D'Addario Chromes, The EC81 set- 45, 65, 80- 100. I LOVE them. They feel about the same, pull wise, from string to string. A great set of flats.
Any heavier, like the 50-105, or LaBella Jamerson heavy gauges, and you risk a lot of tension, especially on a vintage type truss rod necked bass, like my Fender reissues. The high quality Thomastik Flats -the current
'Holy Grail' of flats for many- are far too rubbery for my liking.