I actually REALLY considered picking up the processor from 6spd a while back, but luckily I couldn't find the dvi h/u to control it. Luckily because I have since needed that money. Also, I wanted to keep my d310 at the time to control my iPod and watch video. I called Alpine up to see if there was any way I could just get the h990 processor and use my d310. Short answer was no. You HAVE to have the dvi headunit. So, after 30 minutes on the phone with Alpine Tech (who was very nice, btw) I came to this conclusion:
The amount of money I'd have to spend for a "somewhat" gain in SQ from what I had just wasn't worth it.
Some things you might want to know:
You do not need the TMI screen to control anything. It's just simply there for display. Only the dvi headunit controls the processor.
If you want to use iPod you'll have to buy an ion-bus adapter and go to the OLD ai-net iPod controller. So, you're screwed 2 ways. First being that you have to spend $200 on this conversion unit. Secondly you're stuck with the archaic iPod controls.
I'll echo Kenny & Flip here. More than likely you haven't done all you can installation & speaker choice wise. Your output is limited by your processing, yes. But, you can't get any better quality out of your speakers than they already are. There's no magical speaker that has 100% efficiency so you really should take your time and efforts into lining up a nice set of speakers that if you decide to buy the F#1 gear you won't find yourself needing to replace speakers right away.
Having said all that, if I had the money to spend right now I'd give it a go. I'd at least like to say that I tried it.
I think I'm going to have to disagree with re-sell. Nearly every time I see this up on forums (used) they go quick. BUT, I will agree you're likely going to take quite a hit to the pocket. However, I know Flip is a finance guy so if we put this in percentage I believe your depreciation would be roughly the same as the w200/h701 combo. I'll let him run the numbers, lol. I don't think you'll be re-selling this kit once you get it though. //content.invisioncic.com/y282845/emoticons/wink.gif.608e3ea05f1a9f98611af0861652f8fb.gif
So, my final conclusion? I have no idea. There's a lot to balance out. If you feel that your install & gear is good but your processing is sub-par then maybe the upgrade is needed. But, weigh your options heavily.
FWIW, I'm running the w205/h701 combo starting this weekend.