Probably the biggest obstacle to seeing more units like Schlumpf and HammerSchmidt on the market is installation costs. Even if the already high initial item costs were cut in half - both of those require the BB to be faced and machined. I'd love to tell you that most BBs come at least properly faced - and unfortunately thats not true. Its a rarity even on higher end bikes, and most retail shops doen't even have the equipment to do it.