My experience with fast rate hyd cams is...... The lifters collapse more than "normal" on the opening side, and when the rpm reaches the point where lofting starts to occur, the lifters "pump back up", and if there is any appreciable preload, the valves hang open, and the power drops like a rock.
More spring pressure just exacerbates the situation.

What is required to get this type of cam to turn any real rpm are lifters with extremely tight internal clearances, and a very low quantity of oil below the plunger(limited travel), so enough spring pressure can be used to properly control the valvetrain, without worrying about how much collapse the added spring pressure brings.

Lobes that use longer, slower ramps have less of a tendancy to collapse the plunger on the opening side, so that's one plus if you're trying to achieve a higher rpm, plus the slower overall action requires less spring load to maintain control at any given rpm.

My personal experience is, I have never gotten any fast rate hyd cam to rev very high....... In any brand of motor.
I'll admit, I have zero LS or Gen3 experience though, and those platforms seem to not suffer from this situation as much as the old school stuff does.