The K1 plastic feels lovely in the hand - it is a little softer/bendy than I usually go for, but it works very well.
The flight for me is super straight with a significant fade - it is glidey and rewards you with good, easily achievable distance.
I'm not sure that I agree with th 9/5/-1/2 flight numbers, i've seen a Scott Stokely stamped version of this disc which has the flight numbers 9/4/0/3 - I feel this is a better interpretation of how the Kasta Lots K1 flies (maybe even 9/5/0/3).