haha i come from VW circles too! the reason for the different hyd and mech veedub camshafts was different valve lengths in relation to the cam IIRC so they were a completely different profile on the cams - it isn't an issue of lift and duration, they simply aren't interchangeable as the valves won't lift properly. that shouldn't be an issue on ours though as long as the lifters are the same dimensions.
as for the euro S50B30 the reason for the aggressive cams on the euro model are it has ITBs so you don't have the idle pressure problems associated with a single throttle and wild cams. there really is no comparison between the US and euro motors, they are completely different, and the hyd. lifters aren't the issue.
solid lifters will allow for more lift from factory than hyds though
