I can't stop myself from buying and trying new podcatchers, and Instacast is the best so far. It's $1.99 and does every single thing I want except fling the audio via AirPlay. And that's really a minor gripe. The subscription process is obvious (it even inspects your podcasts in iTunes and offers to use those), and the interface makes sense. My major problem with other podcasting apps is that the interface makes no sense (are there new episodes? how many? where are they?). Instacast has no such issues. It allows downloading for later or streaming, and it obeys the builtin clock timer. Finally, this is not a big thing, but it does the pull-to-refresh UI thing. I just like that.