Dimension (Nashbar) would fall into the same bucket as Formula (IRO), in my opinion. They are very similar and some would argue, not that we should here, that they are essentially the same. I don't think we should debate this either, so since they do have some differences, I think they should go into the 2nd tier.

BTW, I like this thread. Knowing the differences from tier to tier could be very valuable. That said, I doubt we'll come to any consensus, but reading all the opinions could prove valuable.