I made back about half of what I spent by selling catalysts, unslotters, and rare salvage (from brainstorms). If I'd actually sold the ATOs I figure I'd have made around 160-170 million altogether. So no, the ROI isn't as good as you'd get with craft & convert. To me, it seems more like a high-roller's version of swapping merits for converters. And, as Yomo Kimyata points out above, it does scale really well.