The CyanogenMod for Sony's mid-range Xperia SP has arrived, although not officially. A couple of Android ROM developers took it up to task to port the zippy and light custom ROM over to the Xperia SP, and have met with great success. Almost every bug has been fixed and nearly everything is working, save for FM Radio. If you don't use that feature, this ROM is good to go as your daily driver.
CM10.1 brings Android 4.2.2 Jelly Bean to a phone that is still stuck on the now ancient Android 4.1.2. And looking at the leaked Xperia Android update schedule, it doesn't look like the device is slated to receive any official software update to a new version of Google's OS anytime soon. There's a video which shows just how stable and smooth the port is running on the device. Interested users should definitely give this a try if you're looking for some stock Android action.