To be honest, probably Monero.
Why Monero? What does this coin offer that's a head above the rest?
I've been with Darkcoin for a while. But without any bias, Monero does offer the most. From what I've read, it uses Ring Signatures, which allow for both normal and anonymous transactions, which also has the highest level of anonymity there is for a cryptocoin, which is good especially since Bitcoin is starting to get heavily regulated, it's dev team seems pretty large, I've counted 5+ people so far, and its not bitcoin based so none of its features can be copied into Bitcoin. To me, it seems like the anonymous "brother" of Bitcoin. The devs also seem very honest, below quote:
I don't like the forced meme approach either. Even altcoin observer should be renamed monero observer judging by the amount of discussion towards other innovative developments relative to monero circlejerking.. Granted it's not the same pump n dump long con by a team of marketers we've seen before; Fundamentally the coin (protocol, really) is strong, a diamond in a sea of shit, and this time we have cabal (perhaps soon to be monero foundation) of intelligent old heads.. 'bitcointalk allstars', silver stackers, TA tea leaf readers you know the kind of people that have latin in their signature giving it the thumbs up, creating 5 or 6 seperate threads,) boosting trade volume, pulling strings here n there. along with usual brown-nosers following the crowd because it pays to ultimately. I personally am invested for a while, but I've seen time and time again a dangerous insinuation that monero is the one and only and it reflects badly on the speaker,
Speaking as one of the Monero core team members, I can assure you that there will
NEVER be a Monero Foundation. If anyone starts something like that we will reject it, and will encourage the community to reject it.
We are rapidly moving towards a point where every effort - including features, peripheral projects, lobbying, and so on - will be completely community driven and community funded. We will have no control over this process, other than to influence a particular goal by means of weighing in rationally on debates. Any shilling we try do for a particular idea or goal will quickly be called out. We will not have "our" way - the development and future of Monero will be as decentralised as the cryptocurrency itself.