I just started to dive into FreeCAD as an Inventor alternative.

(Are you talking about pre-Blender 2.5? If so, I agree.

It was a challenge going from 3ds r4 and 3ds Max 2... Had to memorize hot keys and get used to a tile based layout. But once I did, I was fast.

The ui was very different, but in a good way, IMHO. The 3D concepts are mostly the same.

But post 2.5, everything is much more discoverable. You can search for commands, pie menus, change hotkeys... and there's great learning resources now.

So I have to ask people that had a difficult time using blender, if they tried it in the last few years.)