Mercruiser 7.4L 454CID Injectors, Marine vs Auto?

My 1999 Carver 356 with twin Mercruiser 7.4L 454cid was having misfires and engine problems. In this video we replace 2 fuel injectors with Carquest truck injectors and clean the other 6 with carb cleaner. WHAT A DIFFERENCE IT MADE! Should I stay with auto injectors at $52 or buy marine injectors for $350? Carquest part #A211-1503 Royalty Free Music from Bensound - http://www.bensound.com