hey fluff, I use them and love them, the 90 lb set. Like I'm sure you know, pretty much the only draw back is you don't want to drop these. But the burn I get while putting them back on the stand is almost like doing an extra negative rep or two.I'd estimate that it takes about 10 seconds longer to switch both powerblocks to more weight vs a dumbbell. Not bad at all.Then also, maybe wear and tear type use goes up with the elect type work, but I like the space savings, so I'm sticking with them.