For quite some time... I have been mining XMR with Dwarfpool, Moneropool, Nanopool, and few more. It was all good back then, but after recent fork of Monero - pools have been changing their payout schedule, increased difficulty made pools struggle for blocks and payment became inconsistent.

I use Poloniex for my XMR address. By the time you receive and sell your XMRs to BTC, you will sent it to your own wallet, ie. Coinbase - so you can count the charges there.

Cryptonight algo has several more other coins not only Monero (XMR) like XDN and BIP.... so I figured that there must demand for Cryptonight hash in their buyer-seller marketplace.

In whattomine.com; it shows that NH Cryptonight yields same profitability as mining XMR direct. In fact, NH Cryptonight has higher profitability than mining ZEC directly -  take a look at whattomine.com today.

So effectively, if I mine at NH, I get BTC upfront and saves me all the charges that Poloniex charges me, and also avoid baby sitting XMR on when to sell off and other buy-low-sell-high risks.

Just my opinion though, if you want to keep XMR coins then this NH method will not work for you.

Afternote: When NH sends you your payment (now once a day to save on tx fees - before its was up to 4 times a day) - the charges is equivalent to 3% which I think it high but I am OK with this as long as they take the risks upfront and pay me for every shares submitted as per rental contract.