Does anybody have thoughts about ebook conversion services?

Hi there! I’ve been researching ebook conversion services, and frankly I’m a little bewildered. There are just way too many choices, and a baffling variety of prices. If any other self-published authors out there have advice or recommendations about which services to use or not use, that would be super cool.

I’ve had limited success converting files on my own, but it seems like I always find some kind of embarrassing formatting error five minutes after I upload my manuscript, then I have to go back and upload it again. For my latest project, I’ve decided it might be worth my while to seek professional help.

So, yeah. Anybody had any experience with converting files for kindle, smashwords, or createspace? Any amusing anecdotes? Sage advice? Horror stories? no