Borini will link up with former boss Brendan Rodgers, for whom he played under at Chelsea and Swansea before moving to Serie A, and Molby feels the Italian's technical ability and work rate will compliment the players around him in Rodgers' 4-3-3 system.
He told the club's official website: "He's exactly the kind of player who will fit into the system Brendan wants to play.
"Technically, Borini is very good, he has two good feet, his movement is excellent and he's a goalscorer. The manager has spoken about playing 4-3-3 and Borini could slot in anywhere along that front line.
"His mobility and work rate is ideally suited to the kind of football the new manager wants to see. He's a similar type of player to [Giuseppe] Rossi, who has done very well at Villarreal after leaving Manchester United.
"There wasn't one Liverpool player who could be happy with their goal return last season. We desperately needed more options up front. We need to be more prolific this season and hopefully Borini will help us achieve that."
Molby has been impressed with what he has seen in Borini, and hailed his attitude to seek out first-team football in Italy after failing to force his way into the first-team at Chelsea.
He added: "Brendan has stuck his neck out for this kid and clearly has a lot of belief in him. I don't think the fact he didn't make it at Chelsea means a great deal. Borini was very young and he had the likes of Didier Drogba ahead of him in the pecking order.
"To be fair, he could have signed another contract and stayed on the bench at Chelsea for another couple of years. But he decided not to hang around. He wanted to play and credit to him for that. He went back to Italy, did very well for Roma and got himself into the Italy squad for the Euros."
Molby feels Rodgers' familiarity and confidence in Borini will help the youngster adapt quickly to the Premier League where he hopes he will shine for the Reds.
He continued: "Brendan will know exactly what he's getting. He worked with him at Chelsea and must have been impressed by him to take him to Swansea. He did very well during that loan spell and his goals helped get Swansea into the Premier League.
"Brendan must feel there's more improvement in him and this is back to the old Liverpool mode of buying a player with potential. At Chelsea they ask their striker to play in a physical way but Liverpool will rely on his movement."