I used a butane torch I got from Harbor Freight. Took quite a bit longer than I thought it would... around 35-40 mins. But I took my time with it, heating it in stages (3 total), starting with a cooler flame on the torch and turning it up after each stage.
I probably could have gotten a more even finish, but I wanted it to have subtle differences to give it a bit of texture in the color.
For a $14
mod, no hesitation to do it, though I did practice on a couple attys first. I'd probably be a little more scared to torch a $200
mod.
I think I'm going to order another one. I'll sand it down to get rid of the logo, then polish and buff it to a mirror finish but stop at the amber color stage. I really wanted to get purple, but it's too difficult.. very small window of opportunity to get that color before it starts to go blue. I think the only way to get it right is in a kiln. I've been eyeing a digital kiln on eBay for a little while now.. only $300...