What are the best alternatives for developing RAW?

This post is merely a question to the cub visitors - not a list of interesting alternatives for Lightroom, which I have already found here. I'm looking for a preferably free and easy to use program to edit the RAW files from several smartphones (Lumia 1020, Lumia 1520 and Panasonic Lumix DMC-CM1, hopefully LG G4 soon too).

In the post I've linked to already, I found interesting alternatives I'm tempted to test, like ACDSee Pro, which isn't entirely free but won't cost mee too much if I decide to buy it. And - for Windows - I find two free programs: Raw Therapee and Lightzone (needs registration). I know Darktable is supposed to be pretty good, but I'm not an Mac or Linux user.
I've downloaded a trial version of ACDSee Pro and of Raw Therapee to begin with and I'll keep you updated about my experiences in this post. I'd appreciate your input however, I'm sure there are many of you coming in here with valuable tips - all one needs to do is ask :-)