All PIKO motorblocks are almost the same. Their construction filosophy: A motor with two gears, and therefore two powered axles. If there's a third axle (like the BR199 and BR80), it is not powered.
So, on the technical side, there's no difference. Both models have three axles, and the same motor. The center axle is not powered, and doesn't have power pick-up.
However, the design is different. The BR199 has a pivot point on top like the V100 {
http://gscalenews.com/images/piko/small/36105.jpg }, the BR80 does not have one of course {
http://gscalenews.com/images/piko/small/36106.jpg } .