Way back when (like 1998 - 2004) when the internet was a new thing and discovery in itself was fun I read
PDML,
jcolwell.ca and
Stan's Pentax Photography (which compiled PDML) and
AOHC and
MIR and
photozone and
Boz Dimitrov and
Fred Sherfy and
Paul Provencher and
Karen Nakamura and
Mark Roberts and the defunct (
but semi resurrected) Monaghan's Mega Cult Classics to learn about the best Pentax lenses to covet. I had a couple hundred Pentax Bookmarks (that got lost when a laptop HD failed). These are the main websites I recall off the top of my head - there are dozens and dozens more. I think the more interested Pentaxians in the late 90's did these to support Pentax - and they're still going. Many of these websites link other websites and you can follow those paths for months - or years!
In general those posters cited long personal experience with Pentax lenses, or comparisons of lenses they actually owned or had borrowed from other PDML members in the same FL. Ratings, though possibly not consistent across focal lengths, were certainly relative within a focal length, so the Best lens in that group probably was the best. The "Best Pentax Lens Ever" probably was a great lens. Those reviews were mostly objective - and since there were several sources, repetition carried some weight (though in some cases one source simply quoted another).
While our lens database is less than consistent and objective it has the advantage of being concise and fast to access. I use it for a quick hit and for new lenses, but I still go back to the old sources for legacy opinions.