Why I chose CodeIgniter <= 3

I'll never understand the constant enamoring of HMVC. I've checked out some other people's projects that used it, and from what I could tell it was just used for organizational purposes, and served no other purpose. If that's really the case, it's not a great reason to include in CI. CI already has great ways to organize your app.

I guess that would depend on the size of your project....  

Last I checked (I could be wrong) MVC is about organizing your code and keeping it DRY.  Managing a 100+ module without HMVC can be a nightmare.  The other obvious benefit is that when you no longer need a module you only have 1 folder/directory to delete.

If you need to revise 1 module - it's all there in 1 folder/directory which is rather convenient.  
I also have a core model with the common queries and the other models extend it and as per the singleton pattern create an instance of it, thus keeping my models lean and DRY.  All too often I see 6 -10 models that are carbon copies of each other.

Cheers,
HEKuiper