For all of you who are not happy with the speed of Nexus S, try using this rom -
I can assure it is definitely much faster than the stock ICS or jellybean ROMs. If you have been using the stock Nexus S ROMS, you will see noticeable difference in the colours. They are much better on this Xperia ROM and does not have that yellow shade. I love the ROM and believe me I have tried almost every ROM available on XDA for for Nexus S.
Though there are 2 issues, for which I haven't found any solution, it blocks the calls coming from unknown numbers and you do not even see a missed call. And you can't use the default screen locks. But apart from these, the ROM is rock solid, never crashes or hangs, everything works fine and it is ultra smooth.
If you think your phone is running slow, I highly recommend this ROM. Everyone should give this ROM at least a try.
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