I am using a Bryton Rider 20, bought as an impulse purchase when my wife was buying her bike. Was £130 complete with the HRM. Disregarding discounts and cashback, it is comparable with the Garmin Edge 200, but with the ANT+ functionality that means you can link HRM, cadence and speed sensors.
I haven't tried the Edge 200 to be able to compare, so I can only give my impressions of the Bryton:
Firstly, it takes a little while to figure out how to operate it, and you really need to download the full manual from their site rather than relying on the included quick guide. I am pretty techie, and I found it a bit tricky, although I have heard that the Garmins are a bit like that too. Onec you have got the hang of it, most functions are pretty self explanatory, and it then seems to work well as on the bike. I have had one or two instances of it not starting to record the ride for a minute or two, but I think that's probably me not waiting for it to get a GPS fix. The centre of the display shows your speed, the top either the time, ride time or cadence and the bottom a selection of other info such as distance, heart rate, etc. You can either select these with the buttons or have them cycle through - I change manually and have found that is supplies all the info that I need during a ride.
Once back home, you can then plug the device into a PC and download the info into the usual array of maps and charts. The connection on the back of the device is proprietary (in order to keep the elements out I would imagine) so you need to keep the lead safe. The interface is rather clunky to be honest, and has a slightly unfinished air about it. I was not able to install it on a Mac, but it does work on my PC. You do get regular updates to the software and firmware though, so it looks like it is being continually developed. An example of the clunkiness is that you can't select from multiple rides on the device which ones to upload or delete, you have to do them all. Also, once you have uploaded and deleted, you have to unplug and reconnect for some reason, which looks like a kludge to me. I run a number of browsers on my laptop and upon reconnecting, it always tries to open Opera, although to be fair, that is probably a local issue. Having said that, once you know what you are doing, it is quite straightforward.
The information that it presents is pretty good, with quite a lot of detail, and the usual graphs of altitude, speed, heart rate, etc. There is also extensive analysis options, which I have not yet fully explored. You can export in a number of formats and I use the TCX to import my Bryton rides into Endomondo, which I used to use, so I can track my total mileage.
Overall, I am quite pleased with this little device, it seems more accurate than my iPhone and Endomondo and gives more info. The HRM works well and I intend to add speed and cadence sensors in the future. One thing to note is that the Bryton speed/cadence sensor is not a combo and can do either speed or cadence, not both. In theory, the device can support any ANT+ sensor and it specifically mentions combo sensors, so it should be possible to use another manufacturer's sensor. I am waiting on Bryton support to confirm this and will report back as and when I get the kit.
I started out whether I would have been better getting the Garmin, but now I am happy that my Bryton does all I need and has the extra ANT+ functionality to boot. Recommended!
Bryton also do equivalents to the Edge 500 and 800 which may be worth a look.
Colin
Edit - Just want to add that I am not affiliated to or employed by Bryton!
but I certainly wouldn't want to be without gps these days. Its a great fit and forget tool for me and lets me pour over stats when I'm in the mood and I like knowing exactly where I've been and building on that the next time 
