I don't have time right now to test it, lots of work ahead of me. I'm personally using UFO and it works flawlessly with that mod. My guess is that it will work with AFT as long as it doesn't place any scripts on player horse. I encourage you to test it and give me your feedback on that matter, just remember not to overwrite any saves in case it turns out to be problematic.
That is something I want to do but unless I can make it work with multiple followers and mods like UFO it won't see the day.

This is the best horse mod to date! Installed it last night and works as promised.

New version is on the way with a very hot and cool feature, independant multiple follower horse support. Good news is that UFO (the most popular mod for followers) is a base for my work and when I'm done it will work with not just UFO but many multi-follower mods as long as they do not force horses to the followers via scripts or such. Scripting methods are used to detect multiple followers without the need to merge with other mods. Work is in final stages and SKSE will NOT be needed for followers to have horses. It is also made as an optional feature so you will still be able to use this mod with your favorite multi-follower mod if compatibility issues arise.
Here is the current feature plan, most of it is already been done:
- General multiple follower mod support but specifically tested to work with UFO. Following subfeatures: up to 15 follower owned and named horses, automatic follower horse management (horse call spawner and bloat-free remover), random or selectable follower horse skins, responsive mounting/dismounting, mass horse call, follower fast combat-ready dismount, followers escape combat by mounting their horse if player decide to do the same thing, distant fast travels while followers are mounted will automatically dismount them so they do not remian at the source location (UFO users know best of this problem).

Stay tuned for ETA. Still waiting for new SKSE version in order to complete custom key binding features so it won't be out before that thing arrives.