good post.
although, you do get more "power" with the phenolic tip. it transfers more energy into the cue ball upon impact.
leather is soft and therefore it gives upon impact, where the phenolic tip does not give as much, therefore transferring more energy upon impact.
personally i have both break cues (not an actual sledgehammer, but has the same type phenolic ferrule/tip)
i can break very well with both of them, although as said previously there are different techniques for each cue.
if you like stroking the cue pretty hard, go with the BK with a leather tip. as you will be able to put more stroke into it and still be able to control the cue.
with the sledgehammer, you don't have to stroke nearly as hard, but you still get as good or better results. some people have trouble controlling the cue with the sledge, although i personally haven't had a problem at all with it.
i did notice that with the sledgehammer, i ran into one problem, i was hitting the rack with what i call "50 yard line power" it was enough to get the rack to spread open well, but weak enough to leave the 1 ball on the short rail instead of around the corner pocket where i'm trying to leave it. so i had to adjust and learn to control the cue while stroking a little harder.
still with the sledehammer, i'm getting as good or better results hitting the cue at about 60-70 percent power than i was with the BK hitting at 80-90 percent..............
VAP