Now that the last handful of PF rechargeable battery packs are selling for silly money on BL I'm looking for an alternative for my next train. If it's not going to be original, then I might as well go for a battery pack with a shape and/or size that's easier to hide inside a steam engine. I've seen BuWizz but that's still expensive and includes a controller I don't need (because I already have Pfx bricks).
Does anyone have experience with third party rechargeable battery packs like the ones that go into RC cars?