It works great. The only caution is to be VERY fire safe. Best to do it outside. Get an old ice cream pail. Put an inch or two of MH in the bottom and drop in your strings. You can leave them in as long as you want but the minimum should be overnight.

I'm a little biased, because I work for ToneGear, but even if I didn't, I would rub alcohol on the strings. Aside from drying out the strings, it'll dry out the fret board, which can lead to cracks. Check out The String Cleaner. Keeps the strings clean without any oils or solutions.