I've owned several of them made with birch shells. They are quite excellent drums which blend in musically very well, much like a Ludwig vintage wood shell. As regards "Can they be cranked..." I believe the answer is yes, but then again everything has its limits. Mine always delivered a warm, crisp "pop", and owners of the later models made of mahogany offer up high praise for them as well.

Had a 60s, 6 lugger that wasn't doing much, until I sanded in a snare bed - been my main snare for months, until I ordered another, 8 lug this time. Loving them both - lots of tune-ability, (slot head Ts though) and feel, and sound fantastic, (to my ear anyway). Currently seems to be a very reasonably priced drum generally - got my endorsement.