For me personally, the speed is probably last on the list why I upgraded to pro (from very start).
The list is something like this:
1) Wanted to support Tyson for what he gave to community, and still gives.
TyFlow was completely free for first 3 years, and free version he gives now is also very generous consider what it offers. I just had to support guy like that.
2) The way licenses works. You license never expires. You can update TyFlow for one year, and if you decide to stop. Your license stays with you at that point... forever.
You can use it with no limitations. You just can't update to newer versions, until you buy another year... and you can do it.. whenever you want.
I with more companies do it like that.
3) Tycache is freaking amazing. In few clicks I can add character, and all small parts, accessories that are attached to him, cloths, and very fast get one tycache file, that I can use within TyFlow (if I want thousands of characters). Tycaches are also highly optimized. They take as less space as possible. Also, even after you're done with caching, Tycache offers some very handy options for scaling, and culling with various methods. It's just amazing. You can't even compare it to 3DS Max built in Point Cache.
4) Cuda cloth is amazing too. You don't need bunch of polygons to have accurate cloth to cloth collisions. It's pretty fast considering what is doing.
5) Finally speed. Practically all is multithreaded. So you will feel drastic difference when fracturing and simulating rigid bodies, or with modifiers, actors.. you name it.
I do understand that the difference depends on every specific PC build, but some average machine tests would be very helpfull (not only for me, I guess 
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