JCL –
Bimmerpost (which e90post is part of) is a huge for-profit business. :cue infomercial analogy:

You will find biases on any forum. However, you are more likely to see honest and open discussion on n54tech. It tends to be a bit more mature of a group overall as well. Yes, it is owned & hosted by Terry Burger of BMS. He makes no secret about it. n54tech is a true open forum where anyone can voice their opinions & experiences positive OR negative. As a longtime member, I have never seen any posts on n54tech be deleted. I can’t say this of e90post where posts and entire threads vanish on a daily basis. If people are looking for information on BMS products above & beyond what’s found on the sales site they wont go wrong on n54tech.

Kloggy -
I agree with JCL, ranking is all relative. The major US tuners in alphabetical order:
- BMS
- Cobb
- Dinnan
- GIAC
- Vishnu (Proceede)