I called Travis at TS Customs with the same question. He builds alot of Lone Peak actions . In a nutshell it was conveyed to me that Ti is great for weight savings on something that won't get shot much and carried a alot . If you're going to shoot quite a bit, especially something big and high pressure an SS action is a better choice in the long run.
I really wanted Ti but after talking to Travis I decided that SS was a better choice for my build and hot loads I typically use.