The best thing about SF, is taunters become irrelevant. Yes, you may have to go through a cycle of toons hitting them, but unless SF is stunned, you know you can remove that taunt the next go around.
That said, in our top 10
#10: The droid squad
9: EP, Wiggs, JKA, SF
8: Rex, JKA, SF, QGJ, Aayla
7: Wiggs, Lando, STH, EP
6: EP, GS(wow, haven't seen him in a long time!), QGJ, RG, STH
The top 5 are the people I usually end up battling for #1. We may each drop at night (rarely below #10), but when I'm up, it's the 5 of us.
#5: Rex, Wiggs, JKA, Aayla (good damage, plus Aayla stun, but he has no taunter or debuffer)
4: Wiggs, JKA, Aayla, RG
3: Wiggs, JKA, Lando, SF
2: (This is me at the moment) Rex, SF, Aayla, JKA, and then the last spot I move around with any number of toons, including Lando, QGJ, 5's, FOTP, Biggs, Mace, Kit
1: Wiggs, SF, Rex, Aayla
Aayla is very popular on our shard for her stun. So, as you can see, 3 Rex leads out of 10. 4 Wiggs lead. 2 EP, and then the droid squad.
My problem is that I get bored with the same squad, so I change a lot. When fighting Wiggs though, unless you have a super fast EP, you almost have to have Rex lead, or IGD lead. I use the IGD lead a lot with JKA, Aayla, Mace/QGJ, and SF.
That being said, Rex/SF combo is definitely a good Meta right now.