Initially I didn't think I liked the pattern of River but I have decided to stay with River. It has grown on me and seems to be knitting up fairly quicly. 62 stitches per row.
I have done a few more pattern repeats today.

A close up of the pattern

I am using Addi needles size 6.5mm. I seldom use Addi's, in fact the only other time I have used them is when I knitted Birch. After 5 attempts at knitting Birch on bamboo needles I decided to try Addi's and Birch never looked back.
Addi’s and Rowan Kid Silk Haze will go hand in hand on my knitting agenda.
The knees are doing grand - each day better than the one before.
Happy Knitting.

Your River looks brilliant - mine looks totally different, is twice the size of yours and twice as lacey.....I am on plastic needles size 6 - all I could find with good points - I tried Addis but found the stitches slipped too much? Think it is because I am a very loose knitter.....
So glad the knees are working....