I think the old argument of Chinese stuff being inferior to US and European aircraft is wearing a bit thin these days, in actual fact the Chinese are proving very go ahead in these areas and one has to consider that many of their military aircraft programmes are not merely aimed at arming themselves, but aimed at the lucrative cheap mid range fighter market which has a big gap in it, that they are intending to fill.
It is wrong to assume that these Chinese aircraft are reliant on Russian technology too. The Chinese know that sales of their aircraft would of course be hurt by a reliance on Russian materiel, and as such then have not created either the J-10 or the J-17 to be hindered by such reliance. This also removes many of the strings that come with purchases in the nature of either the US or the Russians, and the Chinese are well aware that such attachments are a major turn off for buyers if they mean sanctions can interfere with maintenance. This is one of the reasons why the Pakistanis are a major partner, as (notwithstanding their fragile war on terror alliance with the US) their military is not limited by being in bed with the US, or the Russians (as their longstanding enemy, India is).
In addition to the J-10, the FC-1 Xiaolong (J-17 to the West) is intended to fill the gap left by any other aircraft suitable as a viable more modern replacement for the 'second line' fighters of Western and (former) Eastern Bloc origin, namely the MiG-21/Shenyang J-7 and the Northrop F20 Tigershark/F-5 Freedom Fighter.
Aerobatic capabilities aside, success with a combat aircraft these days tends to be more about avionics and missile capabilities than maneueverability. That assuming this capability would succeed was certainly a mistake in Vietnam, with unreliable Sparrows and early Sidewinders, but the technology these days can now (more often than not) live up to what the brochure claims it can do. As such, sustained turn rate is probably not as important as instantaneous turn rate for aerial combat in localised conflicts, that and a combination of helmet-mounted sighting systems and all-aspect missiles with a fast rate of turn can prove a winner, with (more than ever) the aircraft merely being the means to put these in a halfway decent firing position.
Cheap as it is, the FC-1 is capable of launching the AIM-120C-5 AMRAAM and the much more capable French MBDA Mica BVR missiles, with the Mica also offering a close-in capabilty too. And even if these are not available, the Sino SD-10/PL-12, is another option, all of these missiles can integrate with the FC-1's Nanjing K-7 radar (which the PAF claim is a lot better than the APG-66 fitted in most export versions of the F-16). And all this technology is cheap too, with an FC-1 costing just 15 million bucks, which is peanuts for a fighter with that capability, so expect this to sell like hot cakes.
And the widespread use of these aircraft will doubtless lead to more upgraded capability. It is already planned to add ground-attack capabilities to the cheaper FC-1, including the ability to launch the Denel Raptor II stand off weapon, so GPS-style accuracy is in the bag for even this bargain-basement aircraft. One can imagine that the more expensive and far more capable J-10 is going to do a lot better than that too.
Being a joint Sino/Pakistan project, the FC-1 will also equip the fifth generation AIM-9 Sidewinder, and the Boeing Helmet mounted sighting system, which the Pakistanis got when they ordered the F-16 means that this technology is available too, so blaming Israel for a technology drain (as this thread originally did) is only half the story, and it is clear that the PAF purchase has something to do with the F-16 looks of several Chinese projects, including the J-10 and J-17.
All the sales revenue for the FC-1 will of course help fund the much more capable J-10, and it is likely that China and Pakistan (at the very least) will use this method.
Don't underestimate your (potential) enemies. The days of cannon-fodder export MiG-21s with a shaky tube-filled High Lark radar, are long gone.

Chock