Here's a rundown of your best options (Full Disclosure, I'm basically a member of PAN even though I'm inactive right now and only hang out here to post on the boards and bother poeple):
If you're hoping to netgain:
PANLV -- We're probably the best netgainers for average on the server. Last set we finished #2 in ANW behind ESD, a clan much smaller than us (~170 countries to ~60 countries), and prior to that, we won ANW for several sets in a row. We compete for TNW some sets, but TKO (the next option) is just far bigger than us and it's hard to make up the difference. Since we focus mostly on average networth, we tend to do very well in t100s and last set had over 50 of the t100.
TKO -- The big dogs of the server from a netting perspective. They can't carry the same type of ANW that PAN, ESD and some others do, but that'd be tough with 300+ countries like they usually carry. TKO somewhat narrowly beat us in PAN for TNW last set, but before that, they've dominated TNW, winning TNW 7 of the last 8 sets. They're more of a target for suiciders than the other clans on this list, due to their size, and they tend to put up a few giant countries, so they often dominate the t10 in comparison to PAN.
LaE -- A once defunct clan that came back, this is their first set back. They were the class of the server in sets 1-3, but faded into being merely a good clan after a cheating scandal (mostly involving people that are NOT in the clan now) and now they're back, with ICe Man and mrford seemingly being their two top people in leadership now. They were a favorite target of suiciders back in the first several sets, but I'd imagine they won't have the same level of problems they once had, being much smaller now and with TKO being probably the most targeted clan.
Elysium -- A good clan that put up a couple good netting sets and then warred last set. They've proven to be good for netting and below average at warring, but that's often the case with most netting clans. They can't match PAN or TKO for resume, but it seems like a good clan with good leadership and they've done well to stay out of trouble and seem to be on the rise.
ESD -- Your best bet if you're looking for a smaller clan. They won ANW last set and prior to that usually were a top 5 ANW clan. Dragon's the main guy over there and has a few top-tier netters that share the tag with him.
There are several very good clans that normally war that say they're netting this set as well. NBK's the most established war clan on the server and pound for pound, I'd probably still argue they're the best, although they've been beat up by a larger clan in SemperFi for two straight sets now. SemperFi (SF) after warring two straight sets also claims to want to net now. SF's also a pretty mean warring clan and seems to be the dominant warring force on the island that is FFA right now.
CC's your best bet if you're hoping to war, as they've come out and said they're going to kill stuff this set.
Lastly, they're FoCuS, which is loaded with vets and is often an overlooked clan. They often war, but have some guys who are pretty good at netting. I'd say they're probably the most balanced clan as far as having a bunch of guys who can potentially put up either a good netting performance or a good war performance. If you're an old FFA player, some of the guys were the old ICD guys, most notably Crippler, who's the leader of FoCuS.
Lots of options.
As I said, I'm a PAN guy, and I think what our clan offers than the others don't is that we're big enough to offer top-notch protection and top-notch advice on how to best build your countries with the current rules (if you look at the top 10 leaderboard all time, the #2, #3 and #6 guys are all in PAN, as well as the #12 guy, who is that high on the boards having pretty much only played a handful of sets). We also aren't the biggest clan, which means you're less likely to be targeted by suiciders that want to bring down the top guys.
If you want to join us in PAN:
http://www.eepandora.com