I rarely eat meat for the reasons you posted above, but I do still eat eggs and dairy. One of my co-worker's is a vegan. I asked what he thought about the Quorn products after I read such great things here. Quorn isn't suitable for vegans, because I believe it has traces of egg whites, but more than that I'm not sure after doing some reading he directed me to it is something I am comfortable eating. Of course, we all make our own decisions, but I thought I'd pass it along here if anyone else wanted to read it:
The Food Revolution Quorn Adverse Reaction Report
I do know from reading here it seems that several members have had no problems with Quorn, but I just thought I'd mention it.
My main concern with Boca and Morningstar Farms is the soy content, though if I only ate those products in place of when I'd eat real meat it would be fairly minimal. I tend to like the vegetarian products that don't taste like meat - e.g. I'd like a black bean burger rather than an original Boca...