I've used it for years. Tim Cosgrove at Kustom King turned me onto it 5 years ago or so and I've done hundreds of Axis shafts with it and no failures. I used to clean them with alcohol and q-tip swab, but don't even do that anymore.
Heat the hit insert a LITTLE, put some of the hot melt glue (Jim's/Kustom King, it's the same stuff) on the BOTTOM of the insert only (it will spread up the insert as your pushing it in) and then right before it's completely in, wipe the excess off, then use the HIT tool to push in the remainder of the way. I don't cool in water, however leave your shafts horizontal on a flat surface until the insert cools.
To remove, screw in a field point almost all the way and heat the point with a torch for about 4-5 seconds. Wait about ten seconds and then start to pull on the point with a pair of pliers. The insert should come out at that point. You don't want to overheat the shaft either on inserting or removing. Use just enough heat to soften the glue each time. I've never had a problem with brittleness of shaft or glue, so I stick to the just enough heat theory.