They will simply decimate almost any unit of heavy cav.
Wow, thats true!!! They are amazing cavalry killers!!!!! They just cut in pieces any heavy cavalry unit in few seconds!!!! I've tryed agaisnt Equites extroardinary, Hetairoi and Parthian late elite catrafacts, and always winned with few losses!!!! And that seems logical, the blades would cut the enemy horse's legs making them useless....

Just so you all know, our stats for scythed chariots have been completetly redone (actually, they never were done). They have the potential to be devastating (not so much in terms of kills but instead just disrupting the enemy formations) if used properly, but are more likely to run amok and cause problems in your own lines or get decimated by missile fire.
Now that I was happy with the actual stats, lol.... But I'm sure the EB team will do an amasing job with it!!!