Don't install EL29!! That's for the epic touch 4g. Unless you want a brick,lol.
FC09 touchwiz gingerbread is best on battery and incredibly stable. If you root, there are a couple great ones out there. The Peoples ROM 2.21 for FC09, or my own kang of it, Cut & Paste ROM that come in a minimalist "Clean" version or themed version by myself "Crispy" version, or another version or it done by a good friend of mine, " Extra Crispy" version, are all good choices. But if you are looking for more Cm7 is as good on battery as Touchwiz. Cm9 is also fairly good on battery and stable. The cm team also just released Cm10 stable also but still has a couple bugs but still a great daily driver. I myself am addicted to ParanoidAndroid v2.53 is incredible, great on battery, stable, and has lots of cool features to trick out your phone.
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