The thing with the optical viewfinders, is that they depend very much on the format - the larger the format, the better the viewfinder.
Your K-r has a lower quality pentamirror viewfinder; when I said a good DSLR (actually a DSLR with a good viewfinder) I was thinking at the very least of an APS-C pentaprism viewfinder (pretty much any current Pentax model). The K-1 is better than that, but it doesn't appear you're considering to spend that kind of money on "full frame".
I see now you also have a ME Super... now that's a viewfinder! (for a small format camera). Sorry, can't have one on a "full frame" DSLR. Blame the autofocus, which steals light.
And since you were specifically asking about the K-01 - sorry for side-tracking along the question: there's no advantage in buying the K-01, except if you think it's fun (and, perhaps, a smaller size). The K-01 is just a DSLR with it's SLR system removed, and permanently stuck in Live View. There's no EVF support at all - you have to use the back viewfinder.
But some people here have it and enjoy using it a lot, I think.
---------- Post added 29-09-16 at 08:41 PM ----------
P.S. It has begun