My Browning Hi-Power has a 4.5# trigger.
My HK USP45C has the light LEM which is around 4.5 #. Anything less than that would be too light IMO.
My HK P30 is a V2 with a nominal 7.3# pull, but I haven't tested it. As soon as I get the springs, I plan on converting it to the "ToddG special". I was going to convert it to a V1, with a nominal 4.5# trigger, but I'm thinking I'd like something slightly heavier in a defensive handgun.