Brent
In the 6.5 bullets the sierras are ok but all over the scale on weight and bearing surface length. They just require a lot of sorting work. Better are JLK and Clinch River. Both have higher BC (over .600)
Twist for those bullets, 1-8. Some are using the 1-8.5 with a special 136 gr bullet and lighter.
As for a standard 6.5 WSM, (ie necked down WSM brass not shortened) all reports except one have it a big time barrel burner, most list 400-800 rounds max before requiring rechambering. Dan Lilja's 3 groove barrels give about a 20% increase in life according Dan based on the testing he has done and field reports given back to Dan as of two weeks ago when I talked to him specifically about the 6.5 WSM. Dan would like to be able to document any extraordinary information, but he has no proof of claims that are 2-3x over normal 3 groove barrel life and said "do not plan on it". If that issue is no problem, then go for it!
Good luck.
BH