Happy to share some notes on how I cook the rack of lamb. First, I basically use the Serious Eats recipe that they licensed to Anova and that you can find in the Anova app. I cook at 133 (or 132.5) for 2 hours.
Next, a shout out to our friends down under who grow the tasty rack of lamb that I buy at Costco for $18.?? each. THANKS, Australia!
After cooking a 4 rib portion (right for 1 person) SV I make sure to dry the rack WELL before finishing.
Last, I DO use the aromatics (Rosemary, butter and chopped garlic for me) basting process to add an extra layer of flavor to the end result. Not that you can see that from the photo.
Truth be told, rack of lamb SV is dead easy. -- I can't provide any insight into cooking other cuts of lamb, but I'll bet a search of this forum will pop good hints from real cooks.