I'd rather have a trimmed card than not have the card at all. I'm not in it for the value. It's not an investment for me. I'm just a collector. I would not pay full book for an altered card and would not want to be deceived, but if I knew it was altered and the price was appropriate for it's condition, and I didn't already have the card, then I'd consider it.
My Huge Wantlist: http://www.zeprock.com/WantList.html