HELLO ELDAR,
I am sure you will get many varied opinions, pro & con. I glass bead many things on a daily basis; aerospace & aircraft parts. Matter of fact, today I glass beaded 4 Titanium Plenums for some aircraft engines.
I cannot with a clear conscience recommend glass beading for a Honda gas tank. First, irregardless of what may be said, it does take a real master's touch to do the process without removing a measureable amount of metal thickness (yes, even with Titanium, I have seen it made paper thin and even holes blown through the titanium).
The metal thickness on a gas tank is much different from the metal thickness of frames, etc., etc. The gas tank will be much more vulnerable than frame, chassis, or even some engine parts.
I have seen even "professional" workers actually ruin metal parts. Yes, the rust and stains of various kinds will disappear before your eyes as you watch, but then again, metal is disappearing with it. I would venture to say that the bottom of the gas tank would be the most critical part of the tank.
Even the world's best tobacco pipe makers, when making a "rusticated" pipe - - - instead of a smooth finish pipe - - - only allow their best "masters" to do blasting on a tobacco pipe.
Perhaps using a wire brush or wheel in a power tool will cut down on the necessary hand work? That process may remove some metal, but I gurantee, not like sand blasting. Then, of course, the necessary hand finishing with proper grit papers, wet/dry, etc., would be in order to achieve the finish required for a good paint job. I am sorry, I know this is not good news.....
~ ~ ~ jaknight ~ ~ ~