It is just a mechanical nightmare. Not to mention if it is possible to blow the stock 2nd turbo I would imagine it would be possible to blow the $1000+ larger turbos.
Dead on, many shops have tried it - but without something like a Motec it's nearly impossible. If you used the stock ECU, you'd have to custom fab all the valves for the sequential operation. Plus you could have good 'ole shaft twist in #2........
That sucks, I really like the sequential set up. But, why do people get custom twins when they cant' use it as sequential?? It cost more money and not necessary produce more power....