@legoboy
I don't think the JFT is as mediocre as it's made out to be over here. Some official statements coming out of China, Pakistan, and even Farnborrough highlight that.
For example, the Thunder's demo at Zhuhai surprised the Chinese audience there, Wng Cmdr Khalid Mehmood(who's been involved in the JFT programme for many many years) talked about this in an interview on Sept 6 this year. According to him, the crowd at Zhuhai, which didn't know any better, believed the JFT to be superior to the J-10, mainly due to it's superior manouvering. The huge delta wings on the J-10 are probably not very helpful in sub-sonic manouverability(JF-17 actually seems to outdo the J-10 in this). Cmdr Khalid also quoted the Chengdu designers(who had worked on the JF-17 and the J-10) as saying that overall the J-10 was a better aircraft, but the JF-17 had won the crowd there because of superior piloting.
No-one in their right mind would say the JF-17 is equal or superior to the J-10, they both fit in entirely different categories(J-10 isn't a Light Fighter). The real question is, how much of a difference really exists in the JF-17 and the J-10. It's very easy to say the JF-17 is inferior or "bad", but an in-depth analysis of components is required to do a fair analysis. It's important to keep in mind the fact that many components in JF-17's avionics suite were derived from the J-10(or atleast, in some way, benefitted from the work and experience China's aeronautics sector had gained working on the J-10). That means some things like the JF-17's radar, the KLJ-7, have a very similar design to J-10's KLJ-10 - the main difference is KLJ-7's sender/reciever dish, which ofcourse does reduce the performance. The future AESA radar programmes for both these aircraft are also going on in parrallel at NRIET. Ofcourse it's not a one-way street, with advancements like the DSI inlets first being made for the JF-17 and later on moving on to the J-10. I've also seen many experts talk about the JF-17's MMI(Man Machine Interface), being the most advanced of any Chinese aircraft for years before the J-10B was developed. JF-17's pilot-friendly cockpit with large Multi-Function Displays even look much more advanced than the J-10A's 90's vintage cockpit design.
So the point I'm trying to make is, the JF-17's still a pretty capable little fighter, and given the little tidbits of info coming out of China from time to time(like their flight-tests on the JF-17 using the WS-13/A engine) seem to suggest that China also realizes this. You mentioned the F-16(and USAF's large fleet), look at how far the F-16 has come from what it was in 1976 when it first flew. The F-16 has come a very long way over the course of it's life, the Thunder's just at the beginning of it's lifespan. We're still "in the 70's" so to speak, and we're likely to see quiet a few modifications on these aircraft. Look at how far Turkey's modernized F-4/F-5 fleet's come over the decades, we *own* the JF-17 and have alot more freedom to tinker with it, that'd suggest modifications at a grander scale.
Even right now, given that the JFT uses the same frontline missile/weapons suite the J-10B(and even the J-20) would use, like the latest SD-10B AAM, PL-8C/D(or whatever the latest Israeli Python derivative heat-seekers China has), China shouldn't have a problem deploying this in Mongolia. This bird provides vastly superior capabilities to the J-6/J-7s they employ now, and for a pretty decent cost.