lol I have the same RAINBOW bootleg as you.
I have I am... and A BALLADS too, all of them from Alion
First I bought RAINBOW thinking it was original but it ended being a bootleg but I didn't noticed any low quality sounds or anything, except for the credits page and the CD art. Then I bought I am... and A BALLADS because I couldn't find the original to buy them and I loved the covers and the songs that were in these, that's my story.