it's going to vary on your environment, body type and the clothes you wear. I'm a rather stocky fellow and tend to wear an untucked button down or "Polo" type with jeans when I am not at work. Usually in firearm friendly locals. As such I can get away with a Desantis, Raven, Bianchi or Galco OWB holster. With a good gun belt an OWB is the most comfortable IMHO. I find a leather pancake style to aid in concealment. However, when I head back home to NY, a notoriously firearm unfriendly location, I go for the IWB. As mentioned above the Milt Sparks is excellent and often copied. GALCO and Desantis make decent IWBs as well.