I just had the OEM pads replaced at 75,000 miles. For the last 28,000 miles, part of my daily commute has been downhill on a canyon road so I knew I had been using them more than when I was on the freeway.
I think I was at 1.5mm so I probably had a little more left but William at Valencia Honda made me a deal I couldn't refuse! (Calpod knows who I mean 8) )