converting bottle jack press

[Smitty]

A couple of years ago I got a Harbor Freight 20 ton bottle jack press. I shoulda asked here first. It's way too slow and limited for damascus. But the other day I saw a catalog about tools used in auto repair shops. There were a couple of bottle type jacks that used an air compressor and one that used a fluid pump. They were in the the $200 range and from the picture looked like either one could be turned upside down and used to replace the hand pump in my press. They were advertized as being fast, strong enough to lift a car, and came complete with compresser in a closed system. Does anyone have any experience with this kind of set up? It looks like a drop in replacement for my harbor freight press. But anything that looks this easy has to have a down side. Thanks in advance.

[B.Finnigan]

I have been kicking around that idea myself and would also be curious as to the replies.