Northampton beat Saracens 23-9 in the inaugural Premiership Rugby Cup final in 2019 and are aiming to reach a first final since then.
They are eighth in the league and facing an uphill task to qualify for the play-offs.
Dowson declined to single out players who impressed him during the group stage, when they scored 230 points in the six games, with fly-half George Makepeace-Cubitt contributing 55 – the third highest individual total in the competition so far.
“From an individual point of view, what’s been most pleasing has been how emotionally involved and invested all the players are,” said Dowson.
“When it’s somebody else’s turn to go, the support they get from the rest of the group is top level.
“Seeing guys make their debuts and performing really well is a really good sign with regards to our ethos and development plan.”
Despite home advantage, Northampton will take nothing for granted against the Trailfinders, who beat them at Ealing in a group game in last season’s competition.
They are currently 13 points clear at the top of the Championship and beat Saracens twice in their group matches – and could include former Saints wing Tom Collins in their matchday squad.
“They’ve made their ambitions very clear, they want to be eating at the top table and this would be a great opportunity for them to show that they are capable of competing,” Dowson added.
“There’s no doubt that they are (a good side), in terms of the quality of their squad and quality of their coaching and how they’ve performed over a number of seasons now.”
