I owned and used both the 360 and the Metz 48 (which I'm thinking the OP refers to) together for about 2 years. The build quality, swivel, power, and recycle times are what led me to keep the Metz and sell the Pentax (oh, and I wasn't doing as much off-camera flash as I'd thought).
However, both flashes consistently produced great results with my K20D, and the only difference I recall was that the Metz had a "cooler" light for flash WB. The only issues with "wrong exposures" in P-TTL came up with spot metering through a KatzEye screen - and that was the same for both flashes, go figure!