I have a set of the HF ones, since the mid 90's, and used a ton..I sprayed some stuff my dad had back in the day, into the rollers.
Now mine are not the lifting style, just the dolley...but I can easily move them around when loaded...now, my heaviest load as I think back, would have been a '59 Chevy PU...so not a 6Klb Escalade, etc...now mine only saw 4 or 5 moves a week when I used them, not 5 or 6 times a day...but think if lubed well...would have been just fine.
Now mine are not the lifting style, just the dolley...but I can easily move them around when loaded...now, my heaviest load as I think back, would have been a '59 Chevy PU...so not a 6Klb Escalade, etc...now mine only saw 4 or 5 moves a week when I used them, not 5 or 6 times a day...but think if lubed well...would have been just fine.