I've seen Midway on the big screen, but have only seen Dauntless on Blu-ray.
Midway, I believe, is an honest Hollywood attempt to tell the story of the early Pacific war by people that are, for the most part not familiar with World War 2 naval combat. Midway has a much higher budget and it shows on screen. Midway has a number of inaccuracies (especially the Lexington sinking at Coral Sea) and tries to do too much in its 2 hour plus run time.
Dauntless is a labor of love produced by people that appear more knowledgeable about the battle. They attempt to tell a smaller story with a much more limited budget than Midway. Their attempt is hampered by a much smaller budget. As a result, their sets and CGI can't compare with Midway's.
Where Midway uses multiple characters to tell the sweeping story of the early Pacific war and the battle itself, Dauntless focuses on SBD and PBY crew activities during the battle itself.
I thought that the Enterprise was rendered well in both movies, but the CGI doesn't hold up well in Dauntless due to it's smaller budget.
I didn't think either movie was well acted. Each script has its faults.
How do they compare?