I've been in contact with a few builders.
RPI: Doesn't dyno their engines. They can say what they like, but if you can't even tell me where your peaks are... They have no fucking clue what they're building. All they can tell me is that their stuff has electrolytes, because it's what plants crave. If you're from RPI, reading this, and intend to state otherwise, think twice and quit while you're behind. You had every chance to answer grade-school questions, and you couldn't. You fail.
Turner: Great reputation, but failed the test of "if you read this sentence, note that you have in your reply" when I presented the rest of my requirements and why they exist after the initial e-mail. I called, and ended up with a nice lady on the phone who was aware of the e-mail, and suggested she'd have someone get back to me. It hasn't happened yet. Time zones, and all... They've got another couple of days, to be fair, but I did say it's fine to call whenever they like. I'm hoping they get back to me, and it was just a matter of handling things on the phone for more efficiency, but I'd have appreciated it if they actually read the e-mail.