back when engle was grinding their cams I asked engle about hughs spring loads. the guy I talked to wasn't on board with hughs spring loading. I run an engle and use engles spring specs and have no issues. I do believe the howards profiles are more aggressive off the seat than the engles and this is were the rub comes in. the more aggressive the lobe the more spring is needed to control the valve train. if having a fast lobe is necessary then buy cam/tappets set up for wheels.; that is if you don't want to take the chance of grinding up the cam/tappets. I don't do the roller thing because I don't need one, and to be honest I don't like the lobes out there and don't trust bronze gears for long term reliability. no free lunches.