I have what I think is a 1.2. They've bred for me once but are young and still in the "figuring things out" phase. They lay huge clutches and tadpole care seems pretty standard for the Ameerega/Epip frogs. Apparently, the froglets come out tiny, so a small feeder is a important. I haven't morphed out my tads yet, so I can't comment on whether melos are small enough or it springs are necessary. I'll seed the grow out well and try flies also.
The adults are on the smallish side, bigger than pumilio but smaller than most auratus. I have pictures posted on here of a male calling from a film can to give a size reference.
I think they are fine for beginners. They don't seem particularly difficult but are quite underappreciated. One thing I'll say is that they are obnoxiously loud and tend to call in the morning and close to lights out, so probably not a frog you want to sleep in the same room with.
The difference between these and hahneli?...At one point, they were considered the same species. They were split into their respective species recently based on differing calls, ranges, and through genetic studies. They are sister taxa.