Agree with George and Kim. I would also add that I highly prefer Silver Air over Cape, if nothing else for the aircraft they fly.
I'm personally just past the point in life where I'm prepared to be crammed like a sardine with my knees up by my ears into a pillbox with a lawnmower engine strapped to the nose. Been there, done that, don't need to be crammed into a "9 seat" Cessna again unless there are only 5 people or fewer on board, max.
The overnight in SJU can be fun, and you wake up refreshed and charged and ready to hit the ground running on Tortola the following morning. For $1,400 less, it's a no brainer to me.
Silver is not as reliable as Cape Air with fewer options if things go wrong. You also have a wonderful view on the flight on Cape Air. They should start getting the new Tecnam P2012 aircraft soon to replace the Cessna’s.
The lawnmorer engines strapped to the wings are 540 cubic inch engines. Just a bit more than a lawnmower!