The type of RGB light largely depends on where you intend to use it.
For instance bullet or square pixels are great on 'megatrees' or matrices. Square are better for props where you want a flatter finish.
Some people use bullet or square to outline windows or roof, but others prefer C9 RGB pixels as they look more traditional.
RGB strip works well in certain situations, gives a nice straight even line, but is more difficult to work with.
If you haven't already, sign up to the ACL forum then download the latest 101 lighting manual (V3 released 18/04/2018), informative guide includes links to a common source of different RGB lights.
In this hobby/obsession you can never be signed up to too many forums.