Think you're referring to time remapping in AE, I do have a version of twixtor and especially it's slowmotion capabilities are very good, think the program calculates the difference between 2 frames and makes some kind of transition then, even if you slowdown a clip considerably the motion still stays smooth meaning you don't get the "jerky" transitions you otherwise see due to the limited available frames.
Another feature I like about twixtor is the fast that you can add motion blur as well so sudden change in speeds don't look so fake.
Actually there are a lot of things you can change, most of them I haven't even tried. But if you really take the time for it I'm sure you can get kick ass slowmotion out of it.
For instance this one http://www.fotografitti.be/NOAFILM/Pvt.html
was produced for a volleyballclub and the cameramovement had a constant speed first, afterwards I changed it with twixtor. Now this was the first time I used after effects on a project so don't expect to much from it but you"ll get an idea.
Want to know more about after effects; check following link, it's were I got my inspiration as well to produce above clip. It's the only way to start learning AE.