As someone who frequents both LessWrong and is the current "head administrator" of Felicifia, there's really nothing wrong with being a member of both. There's no consensus view of cryonics on either forum. I personally do not have a strong view one way or the other on cryonics (though I have not signed up and currently do not intend to).
I know how it can feel to be debating out of depth. Usually, but not always, my being out of depth has meant that I was wrong. I try not to win arguments, because winning arguments typically means you've already written the bottom line and are unopen to new reasoning, a strategy not very welcome on either LW or Felicifia. I'm not saying that you're doing this, or even that you're wrong (I'm out of depth on cryonics relative to you!), but just issuing a general warning.
And I hope you continue to post on Felicifia! We could use more detractors! I find that echo chambers have no vital safety check against groupthink.
So I recently found myself in a bit of an awkward position.
I frequent several Facebook discussion groups, several of which are about LW-related issues. In one of these groups, a discussion about identity/cryonics led to one about the end Massimo Piglucci's recent post (the bit where he says that the idea of uploading is a form of dualism), which turned into a discussion of LW views in general, at which point I revealed that I was, in fact, a LWer.
This put me in the awkward position of defending/explicating the views of the entirety of LW. Now, I've only been reading LessWrong for <10 months, and I've only recently become a more active part of the community. I've been a transhumanist for less time than that, seriously thinking about cryonics and identity for even less, and I suddenly found myself speaking for the intersection of all those groups
The discussion was crossposted to Felicifia a few days ago, and I realized that I was possibly out of my depth. I'm hoping I haven't grossly misrepresented anyone, but rereading the comments, I'm no longer sure.
Felicifia:
http://www.felicifia.org/viewtopic.php?f=23&t=801
Original FB Group :
https://www.facebook.com/groups/utilitarianism/permalink/318563281580856/
EDIT: If you're commenting on the topic, please state whether or not you'd mind me quoting you at felicifia (If you have a felicifia account, and you'd prefer to post it there yourself, be my guest.)