Thanks much, HawaiianPi!HawaiianPi wrote: ↑Fri Apr 06, 2018 11:55 amSo my recommendations are...
1. For simplicity with good performance, boot from one of the new "A1" class SD cards.
2. For the best overall performance, boot from a USB SSD drive.
3. If you need loads of storage, or need to record large amounts of data, go with a hard drive (preferably self-powered).
There's also no reason you cannot combine devices, like boot from an A1 SD card and use a hard drive for storage.
If you don't mind a follow up question: as I plan to use the Pi as an everyday desktop computer (really), would you advise against using microSD for booting? I've read that the nature of flash memory is not terribly well suited to the high volumes of reading and writing one might get through daily desktop (and internet browsing) use; that SSD drives compensate for this to a degree with wear-leveling technology ... but I don't know if that tech is also in microSD cards (I do happen to have an A1 Sandisk Ultra microSD) or in USB flash memory sticks.
Were it not for that concern, I'd happily run the OS off the microSD and use an external, non-powered HDD for storage [I already have two of these in rotation to backup my desktop files. I like keeping my data files separate from OS files anyway.] Then, if the card gets corrupted, I put a backup card in place and resume my work, files safe, OS files easily replaced.
Since I had assumed this was an issue - I was leaning toward eschewing flash-based memory for booting and OS anyway. I already own a powered SATA docking station for 2.5/3.5 internal HDD, so I figured I'd probably buy a new internal HD and start booting from that for my Raspbian desktop. [I do have some older drives ... 80GB, 160GB, but they're so old, I'm not sure I should rely on them. OTOH, if my own files aren't on them, so what, right? Just keep a clone of the boot disk somewhere?]