I looked around extensively at media player products that one can use to take computer-stored films/videos/music and play them on the TV. This was the one I ended up getting. Anyone who has a large film/music collection on their computer will love this box.
I will skip over its technical specifications (since you can read them above anyway). What I think is important is to emphasise its performance, and firstly I will comment on its streaming capabilities. I opted to not buy the wireless dongle (since I don't own a Wireless N router), and instead I use an ethernet cable to my router. In fact, this connection is basically sufficient, so if you are someone like me who only has Wireless G (54Mbps), you shouldn't worry too much. That said, having the player connected with a wire obviously minimises loss of bandwidth that you can experience with a wireless setup, and I should clarify that my computer is not that far from the router, so I do get decent signal strength.
The biggest test I could throw at the box for streaming was a 6.9GB MKV film (720p, DTS sound). This streamed directly from my computer to the box, and the film stuttered twice in 2 hours - this was when my computer automatically tried to download updates for Windows and the bandwidth was pushed to the limit. Even for a file this size, the bandwidth required is only about 13Mbps - well within Wireless G specs. For most videos (I'm thinking the standard AVI 350MB/700MB or MKV 1.1GB), your router should be able to handle this easily.
However, even if you find for some reason that streaming struggles a bit, there is nothing to stop you plugging an external hard drive in to the box and having files available immediately. The player turns any connected external drive into a NAS drive, so you can access it from your computer and copy stuff directly onto it. I happen to do this as well (for things like shows I'm watching where it's more convenient to have the entire series on tap). In fact, there's nothing to stop you filling up an external drive first and then connecting it to the player.
In terms of playback performance, again this player is excellent. It supports Dolby/DTS passthrough on both the HDMI out and an optical out, so if you connect your various peripherals to an amplifier with an HDMI cable, you have no need for an optical out. You can also set HDMI/optical to downgrade to stereo individually, if your TV/amplifier doesn't support passthrough. The player can reproduce upto 1080p at 60Hz, and can also produce the film-spec 24Hz too. I haven't tried the standard yellow/red/white or component outs because, frankly, you'd be mad to buy and HD product and not use HDMI.
The menu system is simple enough to use too. The remote control is a little fussy, and some buttons are strange sizes - for example the play/stop buttons are the smallest on the remote! But it basically does what it is supposed to.
Overall, I'm delighted with this product, with one caveat. I updated the firmware on it using AC Ryan's "latest" firmware release. This caused my box to not boot properly, or the remote control to work. However, there was a Release Candidate update out there that solved this issue. Basically, my only word of warning is to do a google search on any potential problems other users have experienced with firmware updates, otherwise you could cause yourself some grief. That said, it's actually a good thing that AC Ryan provide this many firmware updates - most companies don't, and it should mean overall that your player has a longer lifespan as newer codecs released should be able to be added to the box.