This is just my anecdotal experience. Twice I have challenged people to pay me in lightning so far, and twice it failed. One was the wallet didn't actually support lightning, the other was (I believe) a routing issue with the person's node.

I use Phoenix wallet, works flawlessly. Strike and Cash App seem like good picks, for a number of reasons, so I recommend them.

I don't think merchants want to figure out how to run their own channel. It's better to recommend options that 'just work', and also convert back to cash.