@SNS3Guppy....mate,u mean u did all take offs unpressurised? Wow,that must be unplesant for the pax no??
The petals or buckets positively provide lesser stopping distance by as much as 27% as against the cascades or sleeves,all other things remeining constant of course. Unfortunately I have not seen the buckets on any engines with a thrust rating greater than 20k....for obvious reasons. Noise emissions and enviormental emission standards(not even talking about economy) stipulate the use of higher and higher bypass ratios for bigger engines. Like someone rightly pointed out earlier,it would eventually be impossible to fit one of those larger diameter engines with the 'bucket type' reversers.So although they provide lesser stopping distance,they are unfortunately limited to smaller diameter engines with a low bypass ratio.
Hope that helped...the rest of your queries have been adequately adressed by the other forum members i presume.
Enjoy the gift of flight!