I'm not sure that your question will be flagged but I started out down the same path as you. I started by learning Rokon, then did a game with the Replica Island codebase, then a few games with libgdx and now am using Unity. I would say up front that the final choice you make on a technology will depend on what type of game you make.
The first thing I would mention about the RI platform created by Chris Pruett (former Googler) is that he built RI as a company sponsored project while he was there. Remember that at the time, devices were nothing like they are now and he had access to almost every device running Android so he was able to build a stable game across many devices. It's a good platform, has some basic physics and helper components but to my knowledge, is not actively supported by continued development. Pruett has since moved on to start a indie game company and now uses Unity3d.
RI uses a binary file format for levels that took me some time to learn. There were no resources available to edit the files to create new levels so I had to build one which I did release (in flash) but it was just basic enough for me to use. I actually continued some development on the editor but didn't release the updates. If you ever decide to learn RI and need a level editor, I could post the updated flash editor but it assumes that you know flash and requires you to run php locally to create the .bin files for the game.
After creating a game with RI, I started learning libgdx. This was over a year ago and the biggest advantage it has over RI is that it's always being improved. It's made significant progress over that time and is still very active, both in development and community/support. Mario is very helpful and is very much available to help (although I wouldn't bother him personally) he does answer the forums as well as many other knowledgeable people. I made a very resource intensive game that ran on many low end devices and was very stable. It has support for box2d and bullet physics, has a particle effect editor, font editor, etc. It's a really nice platform to use IMO but if you want to build a game in 3d, you may find there are less resources available.
At the end of the day, I would recommend libgdx solely for the fact that it's an active project. The other nice thing is that you can prototype for devices much faster running in a LWJGL or JOGL frontend instead of using the emulator.