One more I would like to add to the list: the AoLong V2. It is very stable, but since it doesn't corner cut as well as the others, some people with a sloppy turning style might think it catches or locks. For most people (including myself) don't experience lockups, though.
In my opinion, the HuaLong is the best of those because it's faster, corner cuts better, and it even has semi-squared off corners to prevent corner twists. But because the corners are also kinda rounded also, it doesn't lock up for me.
To choose between the AoLong and the GTS: For a beginner, I would suggest an AoLong V2. For advanced cubers who are sub 20, I recommend the GTS. But there are many many speed cubers who are sub 15 and use the AoLong.