I have a few DAO pistols with hammers - LC9 and LCP - without spurs, but I don't really like to play with DAO exposed hammer guns. So other than the smaller framed internal guns, either my pistols are DA/SA, SA, or strikers - so if they have a hammer, said hammer has a spur.
Frankly, I'm not even a huge lover of DAO revolvers, as much of a revolver fan as I am. I like to spend time with my defensive firearms, so I spend a lot of time at the range with them, where having access to an SA option is very nice. I like the 638 over the 642, although I own both. I don't really care for manual safeties on my defensive pistols, as I prefer to have as few manipulative functions between "oh schitt" and "bang" as possible. So I prefer a DA/SA or striker gun for my carry applications.
I had a Sig DAK, and have several DAO revolvers, but I really just don't love DAO's. I don't love snagging the hammer on my DA/SA revolvers when carrying, never have a problem with DA/SA pistols, or SA pistols, but I'd rather have a shrouded hammer, or at least a knurled or checkered hammer "head" to let me cock it when so desired than to have a pure DAO. I did a custom SP101 with a 638 style hammer (no shrouds, obviously) years ago, it looks like a DAO SP101, but remains to be a DA/SA - I really like that revolver, and I'm planning to do one of my Kodiak Backpacker Redhawks with the same hammer.