Why transfer edge miles to united airlines instead of Vistara or Marriot, if you own amex mrcc or travel plat

[NeerajNegi]

Is it worth transferring Edge miles to Marriot via ITC even when you can get Amex 1:1 Marriott points?

Also I have seen united airlines have more value when it comes to international travel (APAC + US). Value can go up to 6-10 cpp.

What do you guys think? How do you utilise the edge points?