It is not that chique to hijack the PowerLedger topic to promote a possible compatitor.
Apart from that, I just read greeneum website for 5 minutes, and I can already raise a lot of questions about the "vision" even if they have not listed their ICO.
So, I think the word "scam" is always more quickly typed than proven, and this can be done for any project, company  or ICO.
If you want to search and point to "shady" things, you can do that for any project