Living close by to it, visiting The Diner was on my Zomato bucket list. I just find the whole American diner concept very neat and way better of a gastronomic idea than 99% of the fast food joints the US has produced.
I had been here before to kill some idle time with 2 friends, and we shared a cookies and cream cake, and it was damn tasty (if you like whipped cream and diabetes-level of sweetness, it's a treat; if not, probably staying away is not a poor plan). So I had to return there and have a proper meal.
Going straight to the point: The Diablo burger is ok. It has a nice taste and the ingredients were good, but I felt a bit underwhelmed and unimpressed for the price tag it is asked for it. For the same what a gourmet burger costs, it needs to be either bigger or to pack more of a punch taste-wise.
On the other hand, I did enjoy the oreo milkshake (really can't go wrong there) and the pancakes with maple syrup were the best I had during my meal.
The service is good, people are friendly and efficient, quick in getting your orders and checking on you; they were kind enough to bring some extra maple syrup, because pancakes for me need to be drowning in maple syrup. The music is as American as Uncle Sam and the feel manages to ring a certain authenticity to it, with its tables, cutlery, milkshake glasses, everything very reminiscent of that style.
If you want to just have nice deserts, the Diner is a good place to go. The style and the music is, as far as I have seen, the ones that emulate the franchise diner look best. Visit if you want some to have a desert while listening to Lynyrd Skynyrd (I even got me some country tunes, and Balck Hole Sun from the late great Chris Cornell of Soilundgarden fame), try ir out. For something more substantial, I would suggest just one visit to get it off the list, and move on to visiting other places in the area. Were it only for the milkshakes, the pancakes and all those treats, wous ranked the place higher. But when your flagship burger is unconvincing... maybe the Philly cheese steak sandwich will so do it for me. But Philly cheese steak sandwiches always hit home.