I had scalenectomy without rib resection for TOS (R) in 2002 and (L) in 2010. I had scar tissue issues in the L for about 3 years but after break up of scar tissue and therapy I am absolutely fine now. The medical community here in America does not like to to do only scalenectomies as it is not called a complete surgery even though in Europe and other parts of the world Dr's are opting to do scalenectomies in cases that they feel are good candidates for scalenectomies only. I am back to all my normal functions including walking my dog and playing fetch games with him and picking up the 2 gallons of milk from Costco without any pain or symptoms. I am not on any pain medication either. I got off Gabapentin this March and I am still good.
Ofcourse everyone' case is different, I am not against rib removal if needed. I almost had my ribs removed in St. Louis last August. But it was not necessary as proven in my case.
Good luck with your surgery with whatever you decide.