I avg around 23mpg in the city in my ST. On the highway we have seen upwards of actually 35mpg which is obviously over the rated highway mpg.
There are the obvious differences between the two.
Center exit exhaust
18" wheels that are only available on the ST
Turbo EcoBoost engine
200A - Basic seats
No MyFord Touch
6 speaker Single CD stereo
201A - Everything in the 200A
Upgrades seats to partial leather Ricaro seats
10 speaker stereo with 8" touchscreen
202A - Everything in the previous 2 packages
Upgrades seats to all leather Ricaro seats
Exterior mirrors are heated as well.
Only comes with a 6 speed transmission option
You lose some convenience features of the titanium i.e. Active Park Assist, Key-less start
The most popular package seems to be the ST2
Seems most people, like myself only wanted the HIDs but the price difference wasnt worth it. You can do a lot of the things that the 202A package gives you yourself for A LOT less money. The ride in the ST is more performance tuned. The car is slightly lower than a Titanium. I park next to a Tux Blk Titanium here at work almost everyday and my car is noticeably lower than his.