the sessantas are summer tyres as well. i think your thinknig of some of the other vredestein tyres.
i choose them for there grip levels and wet grip.
falkens are good, but i've heard that near the limit they are less progressive.
and the toyos i don't like the soft walls, they changed the design a while back and they just aren't as good as they used to be. they are less progressive and on the last car had not very good tyre wobble. was like driving on jelly.
this place gives some of the most detailed reviews going.
http://www.tyrereviews.co.uk/Tyre/
and if you look at the magazine test reviews the sessantas are one of the tyres in the top 10. falkens and toyos don't even appear.
flakens and toyos are midrange tyres, the sessantas are ultra high performance.