I dont expect to have an online wallet on my pi, the blockchain is only 23% downloaded, and it keeps getting I/O errors - i have a 256GB SD card. and gave up trying to download the whole thing.
but still very excited to see it all working on such low powered hardware.
You'd be better off copying the files over from a PC. Downloading the blockchain is the least of your worries. Verifying the blocks will be stupid long, and building + scanning the DB too. Copying a fully scanned DB over will be entirely easier. I dont see a future in this however. A Pi is too slow for the current backend model. It is very likely it will choke on new blocks. The new backend is a lot more scalable and runs on a push model so it won't choke regardless of how little resources are available for parsing new blocks, but it only runs in x64, which disqualifies ARMs by default.
Lite node with the new backend could run on a RPi, but we're not there just yet.
I have the latest Bitcoin Core on my Pi, I've tried bootstrap.dat, and copying the files from my WinPC - (problem may be I copied the chain state too with no luck) the last time i got to March 2014 blockheight and it corrupted.
I had pity much given up, yes the pi is a little on the week side. I was just surprised to see armory launch it as if it was superposed to be there cute is what came to mind.