The downside of auto-downloading is that your tablet/phone will run out of battery much faster than on iOS. iOS has stand by times of weeks (31 days?), which is wonderful. My nexus 7 runs dry after days, arguably because of the apps I use, or because the OS allows them. I'm unsure which I prefer, though I'd like to be able to configure a trade-off between the two myself..
+1
I use BeyondPod as my Podcast manager and its set to only download when charging, on WiFi and at 7am. No background processing otherwise. I've used BeyondPod for so long that I don't even realize effective it is until reading all these comments. I have over 40 podcasts that are updated. I listen to them on flights, walking, downtime..etc.