Two garages gave me different answers on my 3.6, who do I actually believe?

[grahamcole]

Took my Wrangler in because of a slight misfire at idle and came away more confused than when I went in. The first garage said ignition coils and wanted to replace all six, the second said it was nothing and just reset the codes. Neither of them actually explained why the misfire is happening. A colleague mentioned there's a Professional breakdown of Pentastar 3.6L engine symptoms that helped him understand what he was dealing with, but I haven't tracked it down yet. I'm in Musaffah so both garages were local, which is convenient but clearly not enough on its own. How do you decide who to trust when two people tell you opposite things? And is it worth getting a third opinion, or should I just read up myself and go back with specific questions?