Their bowlers restricted West Indies’ powerful batting line-up to 180-4 on a good batting pitch.
Opener Phil Salt then hit 87 not out and Jonny Bairstow an unbeaten 48 to power their side to victory with 15 balls to spare and put them in a strong position to qualify for the semi-finals from a group that includes South Africa and the USA.
“This has been a good opportunity for England to set a marker down for this stage of the tournament,” Finn said.
“Barring a couple overs with the ball, this was almost a perfect performance from England.
“They batted with power and bowled with skill. They knew that when they got the bat in hand, once they got the momentum, they could take advantage of it.
“Phil Salt played an outstanding and really mature innings.”
Salt said England, who play South Africa next on Friday, “needed a game like that” after their stop-start group stage, which they would not have progressed from had Scotland beaten Australia on Sunday.
“Tournament cricket, in my experience, is all about having the confidence and momentum at the same time – and having a little bit of luck here and there,” Salt, 27, said.
“If we can just keep building on that game by game, we’ll be in a pretty good spot.”
Salt also praised England’s bowlers, who restricted West Indies on a pitch where they scored 218-5 against Afghanistan two days ago.
Jofra Archer, Moeen Ali, Adil Rashid and Liam Livingstone all took a wicket each. Archer conceded only four runs from the 16th over, and Rashid just two from the 17th.
“You don’t need me to tell you how good they are,” Salt said.
“Everybody knows that and the proof is in their records – especially Rash.
“I’ve played with him for so many years now and he still doesn’t get any easier in the nets, so I don’t know how the opposition batters must feel against him.
“He did a hell of a job.”