Mitch, I think the 016 is a great budget transaxle for a mid-engine car. They can be had for a few hundred bucks and they'll live happily behind a most V8s as long as you don't sidestep the clutch a lot or have fat, sticky rear tires. And there are some very interesting and encouraging trends as people continue to develop and improve the 016. But they have their limitations. They require the engine be higher than other transaxle options. The gearing isn't very good.
Think about it - figure you want a real nice 016 setup, so you find a useable core for, let's say $300. You fork over $1,500 for a Quaife LSD. Then you send it off to GTA for a $2,800 R&P and rebuild. At this point you have close to $5,000 into your "budget" transaxle. That puts you firmly into Porsche G50 territory and you are getting close to ZF money. Both alternatives give you a stronger box, better gearing, and the ability to lower your engine relative to Audi boxes.
The 2WD 01E is not available in the US, but they can be easily purchased and imported from Germany. Rebuild should be similar to an 016 and any shop that works on Audi S4s should be able to do the job. As for the strength comparison, I think it goes beyond conjecture - the 01E is definitely stronger than the 016. Heinz Kluge, one of Europe's most respected Audi transaxle gurus, told me it was good for 100 hp more than the 016 in stock form. Looking at mine, this makes sense. All sorts of subtle improvements, like larger radiusing on parts, larger gears, provision for clutch cooling, etc.
All that said, I own both and am installing the 016 in my GT40, at least initially. I will need a new adapter plate, clutch, flywheel, half shafts and shifter mechanism to fit my 01E. I'll do it eventually, but I have all the stuff I need right now to get the car on the road with the 016. I'll report what happens when I sidestep the clutch. /ubbthreads/images/graemlins/laugh.gif