Originally Posted by
Often1
The Acela will be neither cheaper nor faster unless you hit the time just right.
I agree Acela isn't cheap. Using today as example, AA is $99 for LGA-BOS and Amtrak is $206 for NYP-BOS ($107 difference).
However, Acela indeed has the least chance of delay. Its seats, although not coach (there is no coach), can arguably be considered better than coach from any airlines.
Many of OP's travel detail is not known. However, when the conditions are met, Acela may be a better choice than flying.
I won't opt that out just yet.