I'm not surprised. The Exalto A/S (meaning all-season) is not a high-performance tire -- only the name is like Michelin's really good Exalto PE2 and PS2 (the latter has been renamed), but this A/S is just an all-season compromise, and as any compromise, it excels in nothing.

Just after the A/S came out (the year after the PE2 and PS2), Michelin still had a much more informative website in which you could compare the different tires for performance criteria (braking, cornering, etc.) -- one of the best features was a multi-axis graph comparing such criteria, and each tire in a class had a point on that graph with with you could compare tires for whatever traits were your priority. It was terrific as a tire selection tool.
And I remember that the "new" Exalto A/S scored far less than the Exalto PE2 (which in turn was far less than the PS2) -- so, as I wrote above, it's no wonder you're disappointed.

Needless to say, Michelin pulled these informative features from their website. And lacking the Michelin website features, I strongly recommend www.TireRack.com for a future source of good performance test comparisons (as opposed to something like Consumer Reports, which doesn't what performance means) for the next time you pick tires. BTW, you'll see glowing reports for the PE2 and PS2 in their head-to-head comparisons with other tires.

I have to admit that I use the Exalto PE2 on my wife's, my own, and even on my daughter's (at the time) new car (I paid her to have them installed on her car with less than a hundred miles on the OEM MX4's that her S60 2.5T came with, because I love her and I think these PE2's are terrific -- I would have put PS2's on all our cars, but none of us have 17" wheels, the PS2's smallest size). Of course, these PE'2 (and PS2's) are strictly summer tires -- not to be used in the winter -- but it's not a problem for us in N.J., as my wife and I have Nokian Hakka-2's and -5's for winter; and my daughter (in contrast) lives in southern CA, where a snowflake is unheard of. I don't know if having a set of good snow tires is an option for you, though.

You might want to talk to your tire dealer to see if he'll let you trade in those A/S tires for something else. Check with TireRack for your choice.

Good luck.