FrameMaker's stronger for PDF. RoboHelp works fine for generating help from FrameMaker files though I prefer MIF2Go as it's more flexible.
Flare's help search engine is weak or at least was up to 7.1. I don't much care for the way it forces you to put each topic in a separate file. FrameMaker has been going downhill from version 9 on, personally I would be disinclined to buy it. I'm hoping to dump it in favor of Confluence 4 one of these days.
