I've kept a few groups of wild dorsigera over the past few years. The first group I got about 3 years ago and raised out with my discus. The second came to me last year and I've been keeping them with various things -- Mesonauta, Heros, Krobia, and smaller Geos. Both wild groups came from Rapps.
I've found that they can sometimes be shy and skittish, but overall they are mostly peaceful with other fish and have awesome breeding colors. They turn almost completely black with a bright purple/red chest and their eyes practically glow. Here are a couple pictures of breeding colors:
(You can see the male sitting on eggs that were laid in the corner of the tank)
Here's some courting behavior (notice the colors aren't as dark as the actual breeding colors, but they put on a fun display!).
I purchased 6 fish in the first group and still have 3 of them in my 150 gallon. They haven't spawned in a long time. I have no idea what the life expectancy is on these fish. I know rams only live a couple years. Maybe they're just getting old?
There were 12 in my group from last year. They came to me very tiny from Rapps and like a lot of small wild fish they were extremely skinny. It took a month or so to fatten them up and then several more months before any spawning started. I kept all 12 in a 55 gallon. It was definitely a sight to see. There was fighting and spawning all over the place. I had fry in there almost constantly between the four pairs that formed. I have since sent all the F0 pairs to my friend in Connecticut and I kept one spawn of the F1s... they're currently about 1 - 1.5".
I would recommend at least a 55 gallon if you want to grow out a decent group
and keep them with tankmates. Don't let their small size fool you -- they can be really rough on each other. I tried to separate the pairs that formed into 20 gallon breeding tanks with my first group, and the males all beat up and nearly killed the females. The second time around, I left all of the pairs in the 55 gallon and it worked out much better. I think defending the spawning site from other fish kept the pairs from turning on each other.
Another thing to note is that, at least for me, my dorsigera would never spawn in a community tank with other species of cichlids. Maybe there was too much activity and they couldn't get comfortable enough to spawn. The second I put them in dorsigera-only tanks, they started courting and turning dark. They all started breeding within a day or two. I give them little clay pleco caves to spawn on and females will often lay eggs on top, then move the wrigglers inside the cave once they hatch.
Keep them fairly warm (mine stayed around 82F, except the ones with discus which were at 84F) and keep up with the water changes. That's all I've ever done with mine and they bred like crazy.