Most of my fitted IWB holsters are Sam Andrews MacDaniels. Sam's holsters use top grade leather, have very durable stitching, and are spring steel reinforced to ensure ease of draw and holstering against belt and waistband tension. To me, they epitomize craftsmanship.
Disclosure: I know Sam, and he is a quality gentleman.
I recently discovered Remora holsters for unfitted, general transport purposes. They work amazingly well with a reasonable range of pistols in a given holster size, and cost very little. Remora also has very responsive sales reps, and quick delivery.