I have two A2Ks. One with an A2320 and another with a RGB2HDMI setup I picked up on eBay. The A2320 is definitely the preferred solution, but they are very difficult to find these days. The RGB2HDMI also works well, but it was a little finicky to configure. Unfortunately, default settings didn't work for me. Also, about 1 time in 30, it doesn't come up clean on boot and I have to hard power cycle the machine. I think I could add a hard reset switch for the RasPi, but it isn't worth the hassle. For roughly $100 US you can get a full setup with back plate, RasPi, SD card, internal cable, and switches.
