I have 4 suggestions, not in a particular order..
AOSB - people call it a dead project as there are no updates on it since march, but awesome enough to give it a shot.
And everyone's favorite .. Beanstalk.
Not a single non-stock rom for the S2 is 100% stable/bug-free as long as there are no proper sources released from the shamesung for the devs to work with.So don't bother finding one,or just pick the one you like the most and enjoy it.
"Best" or "Recommend" ROM/kernel threads are not allowed on XDA.
Please test these things for yourself.
This is the only way you will get an unbiased opinion,and then, you can decide for yourself if it meets YOUR needs.
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