John,
I've had zero issues with my TurboTechnics turbochagers in 30,000miles+ of boosting between 1.0bar and 1.3bar.
The sequential operation is perfect, I have no oil seal issues, the car pulls very strong from 2000rpm to 5800rpm, EGT's (pre turbine) have NEVER gone above 840 degrees C and that's running 1.3bar.
I am not arguing the efficiency and performance benefits of a small single but that is just not an option for some people.
I don't know why people automatically rubbish the idea of ALL hybrids - my car pulls stronger and faster than either of our two vvti BPU's and has been doing so day in and day out for the past four years.
As with everything else, all hybrids are not the same.