It would be alright for a Trump-Sanders contest, so that Trump could receive the devastating defeat he has coming, but I think any chance of him making it to the final election is a risk not worth taking. Trump is a vile human being, and him making it that far would cause even more people to side and believe his irrational hatred.
A Trump, Sanders presidential contest would be good for America because both men represent the exact opposite of what other candidates have brought to this country, which is $19 trillion in federal debt, a far too high level of people dependent on government for their needs, and what seems like unlimited government intrusion on our lives. Time for a change.
While both candidates have a large supporting base, asking Americans to choose between an extreme conservative who believes Muslims should be tracked and an extreme liberal who wants to create almost impossible change within 4-8 years will leave no where for more moderate voters to turn, and result in either rejection from the rest of the world or ineffective executive power.
If it came down to it, a Trump versus Sanders contest for president would be more of a circus show than about real issues facing our country. Trump's antics might led the Sanders campaign to try and compete with the outrage, making a mockery of the election. It would not offer any diversity in the election with two, older white males running for president and our country is too diverse for that any more.