I've been grueling too! Some of what I've learned..
I too have been looking for the answer to this question but on a different vehicle. I've also done some research on the Opti and I think I'd have to agree with the above advice - that sucker is bound to fail! It did on our Impalla and is (expensive) junk.
As I see it there are about three options worth seriously considering unless you're trying to go really cheap. Those options are the Holly Commander which is a batch (bank?) system that may or may not interface with that Opti, the FAST system which has an added cost sequential option, and the DFI GEN7.
I've found VERY good support for both the Commander and the FAST systems. I've found diddly squat for the DFI, in fact finding people with experience on the new GEN7 has been difficult!
The Commander doesn't presently support a WB option but it MAY in the future. It's pretty cheap but you'd want to make sure they offered a plug n' play version for you car. Doug from Holley is THE guy to ask over on ChevyTalk. I'll post an URL from my thread over there below for you. He supports the Commander as well as the guys here support the FAST system and gives VERY candid answers. I'll buy some Holly hardware, though possibly not their ECU, just to support the company he works for as I appreciate his advice.
The GEN7 and FAST system DO support WB NOW. The GEN7 system appears to support more features out of the box - sequential looks to be included and doesn't require sending it back to the factory for support etc.. However the GEN7 APPEARS to be about $400 more expensive. I say "appears" because it's tough to figure out what you must buy with the GEN7 to have a comparable system to the FAST out of the box. Knock sensor harness? MALF lite harness? DFI also charges for their software and uses a STUPID propriatary (sp?) cable to ensure that you don't pirate the damned software. FAST appears to use a plain Jane serial cable and their software price is $25. The FAST software charge is reasonable, the DFI charge of $225 (usually included in the ECU cost from many vendors) reminds me of the old Electromotive software that cost a mint
Honestly, I'm still deciding on a unit. I've found NO support for the DFI online (yet) but it's specs are impressive (on paper). I'm still trying to research the cost differences to factor them in. FAST on the other hand has been sold a few times which is scary but they DO support their hardware\software well online, ARE cheaper than DFI, but do cost for some upgrades. FAST has released hardware\software upgrades recently, they appear to be healthy for the foreseeable future and aren't sitting on their butt's. The Holley system is a powerful budget oriented option and if they support WB will be terrific for those who don't NEED sequential but want WB. Holley is also most certainly NOT sitting on their butt's either. WideBand is important to me and could be to you too since it sounds like wish to tinker - as I do. Many people will NEVER need WB but I find it's potential, aside for the cost
, to be attractive. If you don't need WB or sequential then the Commander is pretty awesome IMO.
Lastly (finally) - why do you wish to switch away from LT1-Edit? I actually researched the Opti because I was considering using the computer you wish to dump
What's lacking? Appreciate any and all info
Some threads\forums that may interest you ->
http://forums.chevytalk.com/forums/Forum12/HTML/000124.html
http://www.turbobuick.com/forums/showthread.php?threadid=18100
http://www.hybridz.org/cgi-bin/ultimatebb.cgi?ubb=forum&f=20
http://www.hybridz.org/cgi-bin/ultimatebb.cgi?ubb=get_topic&f=1&t=001328
P.S. Some additional data points. FAST makes a demo copy of their software available. DFI has a demo but it's not online anywhere that I can find
Holly and FAST have tuning\install manuals online for review. I've found ZIP in the way of manuals from DFI
WTF is wrong with DFI, full page ads in Racepages but no decent screenshots or downloads on their WEB site?! Is anyone here using the GEN7?