Exhaust Baffles

I want a dB killer for an exhaust.

There seems to be lots of different types/shapes. Can anyone explain the difference to me please. are some quieter than others / are there other benefits:

(Not too fussed about reduction in performance and it’s an EFi so don’t need to be told to rejet!)

Thanks.

I’m assuming the shorter they are the more restrictive they are, so quieter and less performance.

I’m also assuming that the mesh ones are more restrictive than the ones with large holes?