I went to the Running Store in Redlands and had them help me pick out some running shoes. I went home with two pairs of shoes - one pair for my little runs around the neighborhood and another pair to use hiking and attempting to run on trails. The pair for on the road/sidewalk are Brooks Adrenaline GTS 7's and the pair for the trails is a related model called the Adrenaline ASR 4's. This weekend Ellen and I did our Rim to Rim to Rim Grand Canyon hike and I wore the Adrenaline ASR 4's - they were so comfortable for those 45 miles. I am so glad I went to the Running Store and had them help me pick out shoes.
I'll keep wearing my La Sportiva Exum Ridge Shoes for my off-trail adventures because the have the grip I need for scrambling around, but when on the trail those Adrenalines will be on my feet.