I was on a weekend trip to BOS with a friend who has never been to the US. We spend lots of time eating and I made sure we'll get to the Foxborough Five Guys. The burger was good although I somewhat prefer the In'n'Out version. Part of my cajun fried were over-spiced while some were pretty much plain
My friend loved it, though.

I am kinda missing the WOW factor but still they rank high on a level comparable to In'n'Out and Fuddruckers.