When switching colors in a self striping yarn, I normally recommend joining at a point where both skeins are at same point in the stripe. I do not recommend that with the colors used in the sample, because it meant there was a long portion when the MC and CC were very similar and it obscured the stripe.
Urth Yarns, Uneek DK (100% Superwash Merino, 300yds/100g)
MC: 6017, 2 (2, 2, 3, 3, 3, 3, 4) skeins
Urth Yarns, Monokrom DK (100% Superwash Merino, 300yds/100g)
CC: 6064, 1 (1, 2, 2, 2, 2, 2, 2) skeins