I’ve been with Alaska the previous 5 years before switching back to UA as a 1K (same status as pre-Alaska). Overall, I like Alaska much better than UA, however UA has better flight options for me. My experience with redemptions:
*Easier to earn miles with AS, especially with the Alaska CC.
*Premium redemptions in domestic: about the same, slight edge to UA
*Premium to Europe: UA avail *seems* better, and BA with its cost/surcharges is often the only premium option.
*Flights to Asia/Australia: I think AS is much better for premium flights to China, Japan, Hong Kong, and Australia.
*Major advantage to UA for being able to take their metal and the use of GPUs overseas.
*Side note: RPUs crush GGUs