My stepbrother has one of the little harbor freight aluminum it has really been put through a lot of abuse over the last 4yrs. Its still working but will leak down on you.

I bought one from summit racing. Size is the same as the Harbor Freight but it feels better in quality. ( I cant seem to find the link at the moment)

I also have a 3ton Harbor freight that has been used in the garage for years. No problems with it has problems trying to lift the front of a F250 Diesel though.....