The catch cans are no better than the deletes, all (aside from the R-Tech setup) reduce the breathing capacity of the engine (both cam and crank) down to a 19mm hole (or less), which does cause excessive pressure and leads to smoking on overrun/idle.
The R-Tech kit runs a separate large bore breather for the cam and crank gases. No back pressure, no hot oil vapors making their way back in to the turbo intake etc.
Get the R-Tech kit - Cheaper than a decent catch can setup and does a better job