Well, I've been using it only for a moment. The reason is that walkman app always FC on My music tab, so I'm not able to choose music I want to hear

(I know it's not Your fault Sir). Also i1 launcher is not multi dpi (I like 140 dpi instead of 160, but launcher and apps are not centered; it's not a big deal, cause it's only my preferences).
I have mixture feelings about camera and album app - I took one picture, but the quality wasn't as good as I think it will be, since it's ICS based rom - a LOT of noise, and album app from camera (tap on the foto preview in camera) did not respond to me - only black screen but no photo preview. Movie app didn't find any on my sd (but they are there

). These are bugs I found. They're not major, so overall impression is good.
Positive things - ROM is smooth, good looking, and it download also MMS APN by itself, so I didn't need to search for it by myself

It can save a lot of time sometimes. No problem at all with WiFi, mobile data, set performance, contacts etc. So if anybody want to feel taste of Xperia i1 on 2011 line - must have.