For a slow floaty slice return, 4.5 poacher's can punish the return.
For a hard slow slice, no 4.5, and no 7.0's, can effectively poach every return.
Watch ATP doubles. Some guys still hit slice returns, if they start at or inside their own baseline. If they're farther back, they do need topspin.
The reason is time. Starting your return inside your own baseline, on TWIST or KICKER serves, the netperson has little time to poach, and you automatically aim DTL a few times if he's edging towards poaching.
Remember, OP is talking kick and twist serves, which you usually have time to set atop your baseline and move forwards during your stroke.