Two months ago I wrote about my decision to tentatively agree to be a subject editor for the RIO Journal.
The Price (APC)
The APC for a traditionally peer reviewed research article in the RIO Journal is €750 (~\$850). This is significantly more than what I usually pay at PeerJ (~\$300), but only a little higher than the \$695 per article price they recently announced. The APC is significantly less expensive than PLoS ONE (whose APC recently increased to \$1450 and the no-questions-asked waiver fee appears to be gone) and less than SpringerPlus (\$1085) and F1000Research (\$1000). RIO Journal is thus the second-cheapest OA journal I know of. As such I would recommend RIO Journal to people who publish non-bio or review papers. (Well right now I would recommend Royal Society Open Science, since they are waiving their APCs for a while).
Getting "publishing-credit" for my research proposals and other research output
It turns out RIO Journal does not offer traditional peer review for research proposals so posting a proposal there is not very different from posting on a pre-print server with a comment section, such as PeerJPreprints. The main difference is that it would be typeset at the RIO Journal but at a substantial cost (€190/€650 depending on length). No thanks, I'll go with PeerJPreprints or ArXiv or FigShare or just posting the pdf on Google Docs.
An interesting alternative
Shortly after I wrote the first post on the RIO Journal, Tim Gowers announced an arXiv overlay journal called Discrete Analysis. The main difference from a traditional OA journal is that the papers are not typeset (and hosted on arXiv). The APC is \$10 (which is waived for the foreseeable future).
I actually think this is the way forward for scientific publishing long term.
Conclusion
If I write a paper that is outside the scope of PeerJ, and if Royal Society Open Science starts charging, then I might submit to RIO Journal based on the current APCs. This would also be my advice to my colleagues should they ask about OA publishing options. Thus, I'll stay on for now as subject editor.
This work is licensed under a Creative Commons Attribution 4.0