I like them better due to the elimination of the rocker supports. The bottom boxes have the supports machined right into the box, the rocker shafts slide right into bosses that are part of the box. Rocker end play was measured at less than .006 from the rocker to the box which is excellent.
I do not have many miles on them yet, but they have really made the top end very quiet. If you can pick them up at a good price, they are well worth it IMO
Picked up a set off E-Bay. Installed after shimming the rockers down to .002to .004., stock rockers,stock shafts. Easy install and alot quieter and no oil in the air intake at all. Went from stock rocker plates to SE rocker plates to TP boxes and there's no turning back, vast improvment towards eliminating the top end noise.
yes, it's a "straight forward change", you shim the rockers, not the lifters...
there are special shims that fit on the rocker shafts and install between the rockers and supports to eliminate excessive end play.