Best value Pentax Prime in terms of price to glass quality

I just wondered what you would consider to be the best value Pentax Prime Lens in terms of price to glass quality for sharpness and resolution etc if you were to accept the FA31 as being the goalposts, numero uno. So what can get closest to the quality of that lens but be so much better value in terms of price to glass quality?

FA43? FA77?

I am interested in the whole spectrum from wide angles to Portraits and Telephoto Primes.

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Kind Regards,

John

Born in the United Kingdom of Great Britain. I reject EU citizenship.

Pentax Espio Mini / Panasonic Lumix DMC-LX5 / Now someone please sell me their K-5 on eBay for a low price ;)!
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