The problem I see with most of those services is the same one you see with xmr.to. They're mostly using Bitcoin as a payment rail (and a marketing vehicle to target Bitcoin supporters as customers) and then they're going to dump it to pay their costs of doing business (most of it in the case of domain registration). There is no real circulatory economy there.

There's really not a whole lot of difference between using BTC to pay for a domain name and using xmr.to to pay for a domain name (via an even shorter holding period of BTC), or for that matter setting up a domain registrar that accepts XMR as payment and dumps it to pay upstream registration costs (not hard to do at all, but also not particularly profitable).