the hydraulic thing doesn't work; it's been discussed at length on the cr list and it's a no-go.
if the dents bother you take it to a framebuilder and have them filled (depnding on thr tubing they can use silver or brass, or a lead-silver mix for super-thin tubing, but that stuff is toxic.

then you have to repaint anyway, so it's not a cheap solution.

i've heard of the tubing-block solution working, but it's delicate, risky, and anyone who knows how to do it is going to be expensive, and you still have to repaint because the blocks rub the paint off the tube.