FC20 is is a name designation for JF17 thunder, when its used in Chinese Airforce, it may have certain features custom to chinese export desires.....
J10B is a 4.5 generation , superb mobility and agility plane
Its probbly one of the top planes ever created - with modern technologies fully integrated with Chinese innovation.
J10B is like 1.5 F16 block c/d planes, its probbly right up there just below , F22 and sukhoi-30 pleanes agains with GREATER mobility and agility and top go line avionics
And its only going to get even more better
Please don't spread misinformation about things you have little knowledge of.
FC-20 is a JF-17 thunder?...what?
The chinese (by this I mean CAC) designation for JF-17 is
FC-1 (also known as
Xiaolong which means
dragon). But that is the designation of CAC, not the chinese airforce, PLAAF.
Upon entry into PLAAF( if that happens) it will (most probably) receive a different designation (possibly
J9).
As far as the
FC-20 is concerned, it is a J-10...now which one it is, whether J10A or the newer J10 with DSI is an open question that no one will answer with 100% surety. Most probably, and from all the information we have until now, it is that new J10 (with DSI). This new version has been labelled J10b on internet forums but remember officially it hasn't even been acknowledge so we don't know its real official name in china either.
Anyway, if PAF is customizing it sufficiently to meet its needs, then they will give it a designation they want. Or perhaps the FC-20 is a designation given by CAC for export versions of J10.
Also so far we have little 'real' knowledge about it. It probably will have an AESA, J-11 style FLIR and JF-17 style DSI and EW housing on its vertical tale. Apart from that, we do not know much of what will change in the internals of what capability these improvements have made. Its rather pre-mature to speculate too much at this time.