Rhoads hydraulic roller lifters.....

I have no experience with the roller lifters from Rhoads, just with there Hyd. units. There best in ether band aiding the wrong cam smaller or used with a slightly large cam in order to regain a few degrees to expand the rpm range downwards on purpose as part of the build.
An example is to use them with a cam 10*'s to large to work with a gear ratio that is to low with the cam as ground. Once the lifter pumps up, your already in an area of engine operation that wouldn't mind the extra 10*'s duration since your moving down the road.