QUOTE=ofiesens2;265809]From what I've seen, the Turnigy 9x has about the most bang for least buck on the market. I've never used it, so I can't really recommend it, but at the 2 Flite Fest events I have attended I have never met anyone who regretted buying it.[/QUOTE]
The FlySky/Turnigy 9X has really had its day. It's still good as the pretty much the only programmable 8CH under $100 and the fact that there are
many hacks that people have developed to make it into a very capable radio. But, without all the hacking, unless you really need 8CH for the lowest price it's not that great out of the box. You will need to immediately buy a LiFe battery for it because it comes with ridiculous 8AA battery cage - be careful with the battery polarity or you will fry the main board. Also the existence of the garish 9XRPRO - it has its own set of caveats - muddies the waters as to the value.
If you just want something to use out of the box, the i6 is cheaper and better. It's better mostly because the AFHDS2A radio system the i6 uses has more reliable range than the AFHDS that the 9X uses stock - at least according to people who flew both in the same location - but also because the receivers are smaller and have better features. i6B receiver supports programmable failsafe, CPPM and iIBus out and telemetry (although the i6 doesn't do enough with it).
If you hack it, the 9X can take you places the i6 can't but the place you will want to go is the FrSky Taranis which since it now exists (as a direct result of all that 9X hacking) means you would really have to enjoy that journey (ie. hacking radios is your hobby).
The only notable downside of the i6 is that you will not be able to fly Spektrum BNFs with it. You potentially can with the 9X but it takes hacks and money.
At least that was my conclusion, so I didn't get a 9X and went for the Taranis + even though I quite like the idea of the hacks. I bought the FlySky/Turnigy i6 as a gift and also for the high school robot club I mentor.
PS: There is a firmware hack for the i6 which will get you 8 channels although in a somewhat limited way.
http://www.rcgroups.com/forums/showthread.php?t=2486545