has any one checked the reviews of the lenses being discussed ( or ignored ):
you will find both user reviews and in depth reviews
https://www.pentaxforums.com/lensreviews/
as I understand it, there has been great improvements in zoom lenses over the film days
but there are trade offs for not having to change lenses like you might have to do with a prime
and don't forget the HD Pentax-DA 1.4x AW AF Rear Converter
______________________
I like both my SMC DA * 300mm F4 ED (IF ) SDM and my HD Pentax-D FA 150-450mm F4.5 - 5.6 ED DC AW by themselves and with the rear converter