I like Scal and his shooting touch but his defense can be atrocious at times (he got burned by Lewis last year). It's true that he is usually useful to the team and he performed well overall last year. I would like to keep him as a big man for our depth, but it's a bad idea to play him as Pierce's backup in my opinion.
If we cant get a good wing backup by trading Scal and Tony I would do the trade.