An issue with both Sanders and Biden, is the people who urge voting for their choice and then indicate that it'll be just for one term. They have already decided that did to age they'll be too old to go for a second round. They then proceed to prop up choices for V.P.
If nothing else, we are getting to see age discrimination in action.
Personally, I don't want either.
Biden because of his past actions
Sanders because we need a person who might be able to realistically get a few things done and some bills passed during their first term. Sanders is worse than Don Quixote at times.