I used AVG for years and it recently became WAY bloated which is one of the reasons I used to prefer it. It was lite and used limited resources and worked in the background flawlessly. I recently made the jump from AVG to Avast and love it. I suggest trying it out if you are running AVG now. Install it, uninstall AVG and run it for a few weeks and you'll likely not go back.
Now, back on topic. iMusic is no more & Neo Music is NOT the same thing with a different name. Keep in mind that being able to DL free music isn't exactly on the up and up so, much like the Napsters of our time, they will be shut down eventually. Just a question of when really. iMusic had a good run but is no more. Looks like Neo Music can't be found on the market anymore either. There is a third one but I don't recall the name at the moment so perhaps someone else who remembers can post it.
Edit: It's called 'MP3 download' and can be found on the market in either a free or a donate version. Seems to work quite well actually and I prefer it to iMusic overall. Thanks to valdesr11 below for refreshing my memory to the name of it.