You are going to have to trust your ears. I used BDR's under my kestral hotrods and they were not at all compatable. It may have been the combo of my parquet over concrete slab floor with the cones but what I ended up with was an annoying upper midrange exaggeration and a thinning out of midbass - not fun! It's too bad as they threaded perfectly into my speaker. Went to a vibropod-like material and was much happier. YMMV.