Looking at nothing but the specs I would suspect the Medusa to be better than either of the Feigaos, lower resistance and no load draw. Weather it can comfortably replace an XL motor is not known for sure. It's a bit smaller than a Neu 1512 but longer than a 1509, from what I've seen the 1515 and 1521 seem to be the Neu's to have in big heavy trucks.

The 36-50-3300 is doing well in my light(stock) Emaxx, not crazy powerful but enough to make it more fun than the titans.

The weather here this week was a washout so I haven't been able to get any more run time all week, tomarrow looks nice, finally, haven't seen the sun in a week!