Hi Saswati31   I would not recommend to conclude on 75%. The minimum I would possibly consider is 90%. Make sure your different experiences are DRAMATICALLY DIFFERENT i.e. have a very high contrast as this will help to distinguish between signal and noise --> not pepsi VS. coke but pepsi VS. penguin...

Hi there   An external domain can not be captured by Target as it is not connected to your Target deployement. However, not sure what you want to do exactly but you might want to consider Redirectors as described here:   https://developer.adobe.com/target/implement/email/working-with-redirectors/   ...