Has anyone used these lifters ?

Since your going solid, just grab the proper lifter and go. As far as Rhodes lifters go......

The Rhodes lifters are so designed as not to pump up quickly. The idea is to delay the pump up action. This in turn creates a condition that has the effect of making the cam smaller by reducing the duration and lift.

I would not ever use a lifter to help with lift. Or help correct a problem with lift, valve train, or anything of the sorts. If there is a problem, fix it where the problem lies and not with trick parts. That is they ONLY way to do it.

Rhodes claims somewhere between 10 - 20 degrees of duration depending on the exact lifter used and how it is set up. Lift can be reduced up to .020.

How you would or why you would use these lifters is up to you. Sometimes there used as a band aid because something in the combo is out of wack. With the cam itself being to big, or other things like a converters stall speed not being in line with the cam, wrong gear ratio or size tire, etc...

You could try and get mad scientist with them as well.
Making use of there cam duration shorting abilities could allow a slightly bigger camshaft in a hot street set up. The extra torque can help with around town driving and at 3K when they pump up, full cam action returns.

I’ve done this on a single pattern, a slightly to large of a cam in a engine that is an “Extra parts build.”
A Rhodes lifter on intakes only. The effect? A temporary dual pattern cam until 3K where the natural ground cam kicks in along with the reported full return to normal operation of the lifters occurs.

For a spare parts build with not so great matching parts, the lifters helped make it work.