I'd say join the party! To be honest everyone has different setups so you will get some people who have successfully streamed 1080p files and some that have issues... and you aren't using particularly large files by the sound of it. Just buy one and try it, if it doesn't fit what you want I would take it back. There is some great people on the forum to help out with any issues and you can be sure the boxee guys are working hard on making it even better.
I thought the 'hard to see' keyboard side of the remote was going to be a big issue for me, but to be honest I find I'm only playing movies in dim light so I only use the directional side, or the numbers which are better anyway. The grey letters do suck but its not a show stopper.
Running Boxee Box firmware: 18.104.22.16835