Cavan's first four points came from Seanie Johnston but Antrim kept their noses in front through Michael McCann (2), James Loughery and Paddy Cunningham.
They doubled their advantage six minutes later when James Graham hit a flat Cunningham pass to twist his way over, Jamie Foster goaling both tries to put Saints in the driving seat.
As for on the field, having signed new Aussie prop Josh Perry to line up with new joint Saints and England captain James Graham either side of Cunningham, Simmons' side hardly look too shabby in the front row.
And Cunningham admits that he now expects to come under pressure for his coveted number nine shirt, from young internationals James Roby and Scott Moore.