I got both Amazon echo and Google hub for Christmas
Which one should I keep?
Keep both. Don't hook them up. Tear them apart and see what DYI project arises or parts can be used for your other projects. There is no obligation to Google or Amazon to use them the way they want you to.
I don't really like either, but (anecdotally) I've found the Google Home experience to be nicer. I fully intend to get rid of all my current "smart home" trappings when I move, but I have a hard time denying that Google has come in clutch a number of times. Alexa is fine, but there's sorta an inescapable air of consumerism that surrounds using it. It's like you're fighting against Amazon to get the functionality you want most of the time, which is more annoying than it is helpful.
Look on the bright side, at least nobody bought you a Homepod!
Neither. Why would you want a surveillance device willingly planted in your home? Return them both.
Which overlord would you prefer to submit your voice to for tracking?