Did you get the Mag-10 directly from Biotest? If you did not, you may have gotten one of the original formula which tasted like ass (no, I've never tasted ass). The have gone through three changes in development. The first was ass flavored, the second was bubble gum-like which I liked, and the latest one I'm told has a minty taste to it. I don't have much problem with the burning. I can feel it, but it isn't unbarable. It actually seems to subside after you take it a while.
If you can't stand the taste or burning, definately look into One +. It is a very good product. I would comment on 1-AD but I've never tried it.