I thought I would open up a general discussion on the topic of lens focal length selection for prime lenses. And here's the question I pose to you all: For your APS-C camera, which prime focal length range do you prefer for general, all-around, walk-about use, the 30-35mm range (equivalent to the the 45-55 "normal" on Full-Frame), or the 50-55mm range (equivalent to the 75-85 "portrait" on Full-Frame), or perhaps something wider like 24, 20 or 16? In other words, if you had to choose just one prime lens to go out with in your bag, which would it be? I ask this because I have begun to seriously consider adding an autofocus, native prime lens to my collection. While I have now built up a decent set of legacy Minolta manual lenses, manual focus has definite drawbacks in certain circumstances, particularly in family and friends gatherings and action-oriented circumstances. I can admit that I'm just not confident enough in my focusing skills to rely on manual lenses in those situations. While I have the kit SEL18-55 and SEL 55-210 to provide autofocus capability across a wide range of focal lengths for most situations, they are not very "fast" lenses and falter noticeably in indoor, low-light circumstances. So I'm looking at getting a "faster" prime for these and other situations. I am currently leaning toward the SEL50F18 due to (1) its wide max aperture, (2) its OSS capability, and (3) its relatively low cost - cost does matter to me right now. On sale now at US$250, it seems hard to beat. But I also wonder if something like the Sigma 30mm f/2.8 would be a better choice for its wider view, even though it is a stop slower and lacks OSS - on sale at US$170, it is an unbeatable value for sure.