Eh, I'll play. Novel alert.

Pretty much from the beginning I carried my gun on my strong-side hip, going back to when I worked as an armed guard many years ago. That's how I always trained. Therefore, when I started carrying concealed a few years ago I decided to stay with strong side carry because I didn't want to find myself in desperate need of a gun and reflexively go to my right hip only to find my gun was in my pocket, for example.

After that it was experimentation. I tried both OWB and IWB, ultimately deciding that IWB worked much better for my needs. Positioning around 3:30-4:00 gave me the best balance between concealability, access, and comfort.

I also realized, after trying different holsters, that I needed an IWB holster with a reinforced mouth and much prefer minimal or no side shielding (the shield kept interfering with my thumb...worst case, I would trap the shield between my thumb and the slide, essentially locking the gun in the holster).

I also concluded that if I use an IWB holster with snap loops, they have to be one-way snaps. I had a holster that didn't use one-way snaps, and occasionally the act of holstering the gun would cause the snaps to come undone. That never happened with one-way snaps.

I've used the wide-body, VMII-style holsters, and while it does improve comfort and lowers the profile a bit, I've actually come to prefer more of a Summer Special-style, minimal profile holster. My current EDC holster is a Side Guard Quick Clip IWB holster with a reinforced mouth and a minimal profile. The offset clip, positioned behind the cylinder, keeps the profile low while pulling the gun butt into my body for better concealment.

Another thing I found out was that, when carrying a revolver IWB, I much prefer having the gun positioned such that the cylinder is in-line with my belt. It may seem counterintuitive, having the thickest part of the gun directly under the belt, but I found it helps keep the gun stable while still accessible and concealable. Much higher and the gun would want to tip out. Much lower and it can be difficult to grab the grip when drawing.

As for gun choice, it was mostly financial. When I started carrying I had a 3" 65, a 2" 64, a 642, and a Glock 23. At some point I decided to consolidate "platforms" and calibers, so I sold the Glock and stuck with .38 Special DA revolvers. My financial situation took a bad turn and I had to sell a couple of my guns, but decided to keep one. The 642 seemed to be the most versatile option I had, in terms of carrying concealed, and I probably would've gotten less return on it, so I kept it and sold the other two. I regret that decision, but one has to do what one has to do.

The 642 works for me, and has a lot of strengths that fit my personal situation. I'm not opposed to carrying a semi-auto, and would like to add a concealed carry semi-auto at some point (a Sig P239 in 9mm would be my first choice, but a Glock 19 would probably be a more practical/cost-effective choice). I have a Beretta 92FS, but I don't have any decent carry gear so until I can get a good holster and mag pouches it will fill a home defense role.

That's how I figured out what works for me. YMMV.