It appears that the HQ-9 and FD-2000 canisters have changed from the cylinder to this octagonal sides.
You don't need rumors for that.
The airframe resembles the 5V55 and 48N6 missiles used with the S-300. However, the radars used have totally no relation to the Russian system. The HT-233 fire control radar resembles the Raytheon MPQ-53 radar for the Patriot missile in concept, but again there are differences. The search radars to support the system are totally indigenous, and uses a variety, such as the Type 305A (AESA, S-band), Type 305B (FRESCAN, S-band) and Type 120 (FRESCAN, L-band).
One big difference is the frequencies used by the two systems. The S-300 uses X-bands for fire control via its phase array radars like Tombstone. The HQ-9's fire control uses C-band, which is what the Patriot and its partner radar, the MPQ-53, uses.
So once you get past the missiles themselves, the supporting systems, which are very important for the whole thing to work, are very different.
Likewise, you can say the same thing about the HQ-16 and the Buk missile systems. Once you get past the missile, all the radars, launchers, everything else, are completely different. Radars to support the land based HQ-16 are totally indigenous.