Being a Pentax Screwmount freak, I would comment: In general these lenses are some of my favourites to work with and rival Leica for sharpness and what I call soul.
28/3.5, 35/3.5: an amazing wide angle lenses
50/1.4 Totally badass for colour negatives
55/1.8 a great workhorse unlike the previous comments, touch wood I have not required a lens hood in my shooting, it might be the case for some of the early Takumars
135/3.5 Fully manual Takumar, came with my Model K kit I got on consignment a few months ago, again, I am biased a great telephoto. This one is totally manual with its settings.
Now comparing with different brands is tough, I would put them on a similar level to Leica for sharpness. Compare to Nikon F mounts and Canon FD's of the same vintage or modern lenses? I don't think modern lenses are any better, in fact I would contend that comparing shots I took with my Canon Rebel 4 years ago with what I took with my Spotmatic II recently, the Spottie would win hands down.