Rhoads lifters

I think they mean you can use Rhoads lifters with a solid cam and it will still work, much like using hydraulic lifters on a solid cam to save the cost of getting a matching cam/lifters. Rhoads lifters are a cool idea but you'll never quite get as much lift at the valve as the cam calls for (even at high RPMs) because of the bleeding down effect. Personally I'd be a little leery running lifters like that just because it would be a big potential source of oil pressure loss and lifter/cam lobe failure. Just select a good dual-pattern, fast-ramp high performance street hydraulic cam and be done with it.