Right now this is the most profitable for BTC because it mines scrypt, then auto exchanges to BTC.
The question is for how long it will be more profitable. With every Hashlet being added, the Litecoin (and other...) difficulty increases and because of the automatic exchange to BTC, it also creates more and more selling pressure on Litecoin making the price go down.
Same case with bitcoin, merchant that except btc also selling btc for fiat.
But for long run, the with increase of coin circulation, the selling pressure will be ease for sure.
My concern is the future of haslet its self. its reliable for long run