Well, I just pulled the trigger and bought a 740b.
Factors and considerations in no particular order:
740b is more expensive than an iPad mini, but the mini is even dimmer than my big iPad. The bright screen of the 740b will be a big plus. On the minus side, the mini could be used for more stuff. But again, it's dimmer. And the 740b is "just for aviation", which could be a big plus because other junk won't get installed on it.
I did finally get that old 720 (that came with my airplane) working. It's SD card was in a stack of other SD cards in my drawer, so at least I could get a feel for it in the air. I imagine the 740b will be everything that the 720 is, and newer/better.
740b doesn't run ForeFlight, but from my newbie perspective it is still pretty good. iFly GPS seems to review quite well from those who use it.
740b is not welded to Apple hardware. This is important to me. Honestly, I would not own an iPad if not for ForeFlight. My old iPad worked fine, until it became "obsoleted" and unusable to me (even though nothing was wrong with it). It's a nice piece of hardware that's been rendered useless by Apple.
I did shell out a lot of money for the "new iPad" that's recommended by ForeFlight, so I'll have both the 740b and a new iPad at the same time. It chafes me a bit that the new iPad does not feel as "solid" as the old one. My gut instinct is that it won't last long before it breaks, or I drop it, or something will happen to it and then I'd be looking to replace it (with something!) anyway.
I have had my iPad overheat - in Minnesota. I now live in Texas. Reasonable to assume that heat related issues will not be any better in Texas than in Minnesota.
My iPad locked up on me once in the air. I was on a long cross-country, and had diverted for weather, and was in unfamiliar territory and off the edge of my printed paper chart. My cell phone (with Avare which I had fully updated for use as a backup just in case of something like this) was enough to get me a line of bearing on my destination, so all was ok. But I remember that the iPad let me down..
I also loaded iFly GPS onto my old iPad. Yes, the old iPad that no longer could run ForeFlight. But again, the iPad let me down once in the air, and I want something new and "dedicated" to aviation.
If I would have went with an iPad mini, I'd still have a "single point of failure" with two devices running Apple/ForeFlight. I don't know much about the recent Garmin hack, but I know it took down their network for several days. I think maybe there is a lesson there for us all.
So there it is. Looking forward to recieving my new 740b.
- Patrick