in the other side, i think that with some improvements it could be the good alternative soon ( if they improve it a little bit )
With an Rpi2, you need either a USB device (which disconnects regularly, it's common with USB media) or an SD card to continually process the blockchain. Neither are a decent solution imo.
Even with an SSD over USB, it's still a bit of a clusterfuck
With Bitseed, https://bitseed.org/, we specifically chose a board with SATA port for this reason. This has given us the option to offer 120 Gb, 320 Gb, 1 Tb SSD hard drives in the $129-$199 price range and have also shipped SSD on special orders. We have seen the 160 Gb drives on our initial units we started shipping a year ago fill up while upgrading to the newest version of Bitcoin since we keep a backup of the blockchain and indexing and the default update process on Bitcoin causes it to temporarily exceed the disk size unless the backup blockchain is deleted first. We have avoided shipping units with only SD storage since SD cards have been reported to fail within a year, often a few months when used for blockchain storage.
We are also pursuing extended capabilities for running other apps on top of Bitcoin, such as Blockstack, and have run other coins as well - Crypti, a node.js platform which runs Dapps written in js on sidechains, https://crypti.me/, NXT, Peercoin, Blockstore, Litecoin, and Dash. The biggest hurdle is RAM, and going from 1 to 2 Gb adds at least $50 to the parts cost if we want to keep the SATA port. We see fairly low CPU activity after initial indexing, so having more CPU cores (we currently have 2) doesn't not give much speed advantage after indexing is complete. We are anticipating that 2 Gb RAM boards will come in at the same price point sometime in the next 6 months to a year.