you ought to know this.

when you let someone record you for free then they own that recording, not you.
normally when you pay them their fee, you're not just buying studio time and engineer/producer time. you're also buying the rights to that recording so there's no problem with you reproducing and generally using it for whatever you like.
if you don't pay for it then the rights probably aren't transferred to you and you don't own the recording. this means that you can't sell or use the recording without the owner's say-so, and that could leave you owing the owner some money.

now if you're a small local band who aren't yet making any cash, you'd be unlucky to be screwed over in this way, simply because you're not making any money and it wouldn't really be worth the effort. although it does happen.
however, when you become rich and famous, you could find the owner selling the recordings he's made and you'd have to legally fight to prevent that; or maybe suing you for using his recordings. either way, you're lining someone else's pockets and not your own.

basically this means you should suspect anyone who says they'll record you free of charge.

but ravenwing will not take your recording rights
for your donation we will give you the recording on a cd and freely and explicitly transfer the rights of that recording to you. then if you like, we'll give you and/or delete the master recording and mix projects too (or we can archive them if you wish).

all we ask is that we be acknowledged as making that recording by some writing on your cd and permission to mention you in our results page. and tell everyone you know how good we are.

ravenwing will not rip you off.