Given the retrieval costs, it seems to be that Glacier is better for an "if all else fails" backup. A cheap-to-store, last resort when your other backups fail. Still, it's nice that Arq calculates the retrieval fee for you.
(I'm the guy behind Arq)
Yes. Unless you want to retrieve very slowly, in which case the "peak-hourly retrieval" fee is lower. Or retrieve just a few things (and stay under the free-retrieval maximum).
