How many of you use multiple AF points?

[ajf]

Was looking around at new bodies and the likes of the 7D etc that have multiple cross type AF points.
How many of you ever use these in groups, or auto rather than just choosing one specific point?

Reason I got looking was an itch to change my 600D. It only has a central cross type AF point but I rarely manually select any other.
How reliable is a group or auto AF points really?
I am thinking motorsport or aircraft mainly.

 

[ajf]

Thanks.
Some interesting points and comments to consider there.
I do occasionally select points but was really wondering whether more actually helped or was simply a 'selling point'.

The ideas of grouping points sounds useful though having read more in some reviews.

My idea was to maybe get a used 7D or the new 70D. Both seem to have the same AF system from what I could find?

Other reasons too for buying anyway.