I listened to the books on CD while driving home from work and enjoyed them quite a bit -- enough that I relistened to the first book right after finishing the trilogy. I think I would have had a hard time actually reading it "on paper", so to speak, for a lot of the reasons that have been stated.
I am sad that there won't be any more because there were some ideas started that I would have liked to see if anything came out of them -- like the entire sequence at the hotel, at the start of the second book? I feel like that could have been forshadowing something for future escapades.
There were also chunks in the first book that seemed to be unnecessary information but did became relevant in the later books. Over the second reading, I had a sort of ah-ha moment because I had forgotten one of those pieces and hearing it again suddenly made a later event click for me.