I had the f/2.8 version of the 30mm Sigma prime for several years and found it to be a brilliant and underrated lens. It was one of the sharpest lenses I have ever had or used on any camera, and in spite of the relatively slow aperture compared to the f/1.4 version, it was significantly more compact - and surprisingly useful for available light shooting. I originally bought it because some years ago Kirk Tuck was raving about both it and the larger 60mm Sigma, and going on and on about how great they were, and how inexpensive as well. He was right on both counts. It's a lens to consider
For sure. I see a few used ones online for a nice price. I really liked the Sigma 60mm and thought, "how far behind if at all could the 30mm be?". But when the time came, Sigma had a sale on the 30/1.4 and it was close to the same price as the other f/2.8 lenses so went with it. No regrets, as the 30/1.4 is a great lens. As you say though, for the price and the more compact size, the 30/2.8 is looking very attractive. Now, I need to research the 19/2.8 and see if that is also a worthy contender!