That is kinda what I use on my personal car - metal straps Dzused inplace over Pig Mats. I also have one on my belly pan under the transmission. I have also seen metal mesh screen used to retain the pads.
I am a part-time tech inspector at the once-a-month Heads Up series at our local NHRA track where diapers or pans are mandatory on ALL classes. I have been asking some of the top competitors which they prefer - diaper or pan? I'd say it runs about 60/40 pans to diapers.