My preference is none. That said i use some irish moss and if i really want to try to rush clarification gelatin. Honestly i quit worrying about it a few years ago and in time most beers clear well enough for me.
I've been using Whirfloc for about the past 6 months and honestly, I can't tell it does much more than time would. For super clear, quickly, I'm with @Head First all the way with gelatine. But I could kinda less and once the Whirfloc is gone l will probably go back to nothing.
Oh man, I've used Irish moss a lot but a lot without it too however I always cold crash. I have never tried gelatin but since others said it works good I'll have to try it!
Anyway my beers are usually pretty clear.
Run out of seaweed a fair few batches back and havnt bothered getting more I'm settling with no finnings these days beer tastes the same to me just takes more time to clear.
Was using Irish Moss, switched to whirlfloc when I ran out..haven't noticed much difference between the two, of course my grain to glass STARTS at 5 weeks so, as the Stones said...."time is on my side, yes it is".
Irish moss in the last 15 minutes of the boil and gelatin a week before bottling if I remember. I find the moss works best if I give the wort about 30 minutes or so after I finishing cooling it for everything to settle out. I put a piece of 2x4 under the front edge of the kettle to encourage everything to settle away from the siphon edge/kettle spigot. The gelatin...the first time i used it I found such a drastic difference in clarity I could hardly believe it.