You should go and check them out at least. But if they really are teaching so many of these rather important things that you disagree with, is it wise to get involved with them? When you surround yourself with what you consider to be false doctrine, it's really hard to keep on resisting it! One or two little things, maybe. But you've mentioned quite a few pretty big issues here if it turns out they really are like this.
This scripture came to mind after reading your post:
2Corinthians 6:14 Be ye not unequally yoked together with unbelievers: for what fellowship hath righteousness with unrighteousness? and what communion hath light with darkness?