IMO the only downside to a hydraulic is you would see less net valve lift than mechanical due to potential aeration of the oil. For that you would have some degree of compressibility, otherwise liquids are mostly incompressible. I think this would to some degree be compensated for by no lash.

The cam was single pattern 3705 lobes. (236/236 @.050). Twin turbo. Open was 450. thick wall 3/8 pushrod. So, not much lift, only .612. 1,340 rwhp