Efficiency wise Tejas would be the best one there are many advantages which other planes do not have.
a) Building the plane builds up INDIAN INDUSTRIAL BASE for AEROSPACE.
b) No more total dependency on other countries for fighter planes (read France, Russia or USA)
c) We can develop and use our own avionics and weapons at no extra cost (we spent nearly 1 billion dollars on just customisation of Rafales for India specific weapons)
d) Can be tailor made for our usage and specific requirements
e) The cost of using, maintaining will be at least 50% of Rafale and effectivity wise much more effective than Mirage 2000 (said by the pilots testing Tejas who have a lot of experience flying Mirage 2000)
Thus at cost at which India procured 36 Rafales we would in a way purchase at least 72 Tejas (just the flyway costs) The cost of building base, and cost of tailoring to India-specific weapons is saved in a way, Or basically the cost saved in India specific weapons can be utlised for buidling quality bases. In a way considering the package what we paid for 36 rafales (minus the weapons) we could easily take almost 4 times the nos of planes including performance based logistics ..
This is efficiency... Lets understand few things, In event of War with China, neither Rafale nor Tejas can hit targets in Guangzhou, just Su-30 MKI can. So in terms of targeting China, Rafale is a dud,. In Western sector Rafale can do well because Pakistan is smaller country, and since its small country even tejas can hit targets in Lahore or Islamabad. So Tejas can handle the role too.
Rafale can carry more load and has better range, but just because it has better range, we wont go to Afghanistan to hit some targets there, So Rafale can hit targets in Islamabad, so can Tejas, and for one mission you might need say 4 Rafales and for the same load we might need 6 Tejas, and this becomes more efficient use of assets, Do remember that France still flies Mirage 2000 almost twice more than Rafale because flying Mirage 2000 is much more cost effective than flying Rafale.
So yes its efficient. What makes you feel China is not selling. They are selling. By the way, China has produced more J-10 than Rafale,, so from 2002 to 2018 thats 16 years they produced about 400 J-10. On other hand since 1986 to now that is about 32 years (twice more than the production time of J-10) France produced less than 180 Rafales. Talk about efficiency ...
J-10 16 years approx 400 planes
Rafale 32 years approx 180 planes.
Need I say more?
In the economic sense there are buyers and sellers. Sellers being America, Russia, France, GB/Germany , China etc and there are buyers Middle east buyers, Asian buyers, south American buyers ..
The Middle east buyers have money and can afford any plane, thus anything from F-35 to Su-35 is possible, they are purchasing Rafale and Eurofighters because F-35 is not offered to them. They also have a lot of F-16s
The South American buyers, they are not in active conflicts and so they do not prefer to spend so much on defence, thus they go for planes what are cheap, Venezuela wants to be out of American influence so they purchase Su-30 , Brazil wants to be a super power of South America, so they wanted to get a good plane, cheap to use and fly and yet capable, Thus Gripen became the obvious choice, Brazil does not desire to attack Mexico or the USA. Asian buyer also like good planes Thailand has territorial conflicts but not going to escalate. They also are good friends with USA to they buy American, and also buy Gripen which was cheaply avaialble as compared to Rafale, They need short range planes and Gripen suffices. Indonesia is group of Islands and protection of these islands is critically important, the aggressor here are the Chinese. The Indonesians are not in good terms with USA, The Eurocanards are expensive or short ranged and hence the obvious choice comes the Russian MiG-29 and Su-30/35. Malaysians are also buying Russian planes for same reason. African countries they have small conflicts and even few MiG-29 end up being superior. So in a way, Chinese J-10 has few markets like Pakistan only, but even Pakistan cannot afford to buy a lot, but on other hand J-17 becomes the right alternative for many small countries which really dont require credible air power just enough to help their territorial claim. So these countries will be Bangladesh, Sri lanka, Maldives, Afghanistan and African countries and China is selling these.
So China prefers to export J-17 because there is good market for these where the likes of even MiG-29 become too expensive. J-10 will end up being a little cheap than Gripen, and those who consider J-10 might spend a bit more and go for Gripen.
I guess now you know why Rafale does not get into numbers right? Or you are still ignorant?
Yes for the price.
But what about efficiency? If the price was the main point, China would have sold hundreds of J10/JF17