From the top the fit and finish was looking unlike a soviet or Russian plane for the first time. But from below it is same old Russian manufacturing. The problem with missile bay doors not aligning properly still looks to be present. Even the Indian serviced Su and Migs looks better then Russian ones. They need to work a lot on their manufacturing practices.
It has nothing to do with alignment, the weapons bays have a tapered inner edge hence the look or appearance of a gap. The alignment on everything seems very good on the serial model. Some of the earlier prototypes had some poor quality but that was mostly because they used old manufacturing techniques just for the sake of getting the aircraft airborne to test aerodynamics, avionics and performance.
The lower part of the fuselage, specifically the cowlings, resembles the SU-30/27 but I would not say the manufacturing techniques or materials are the same. The criticism I have is some panels, still don’t have the sawtooth edges; I think this makes it look more antiquated. It’s very annoying and confusing how Sukhoi decided the add serrations to some panels but not others.
Here is a close up of the underside of the mid fuselage:
The quality seems really good, but again the lack of serrations are present. I still can’t wrap my head around the fact that Sukhoi still has round protruding censors, some fanboys will make wild excuses that somehow RAM will magically negate the shape but that is delusional and not based on reality and science.
As for HAL manufacturing, I don’t see where you get the idea that HAL manufactured Sukhoi have some better manufacturing techniques, if anything there has been a number of Indian built Sukhois that crashed due to Indian components/QC.