I've been with Smashwords, as an addition to the excellent Kindle, since 2013. It has always been a nightmare to publish novels on here. You just have to get the slightest thing wrong and your novel is refused. The Guide is just as useless. That said, the support staff are excellent and patient, and in the end (usually after a month of trying) they will do it for you. Smashwords has a fantastic reach, but once I had my books up there, the idea of amending some text, fills me with dread and I leave well alone. If Smashwords works for you, congratulations.
(review of free book)