I've hit this place 4 times now. It's right down the road from the Clam Box. When I see the line at the Clam Box sometimes I just can't cope and have been using this as a backup.
Atmosphere: Order at a counter, grab your own soda. Also have a fish counter. In other words nothing fancy. Has limited outdoor seating with no view. Really reminds me of Yankee Lobster on the waterfront. Generally little to no wait, even for weekend lunch.
Food: First time I had the clam plate. Passable. Decent batter. Clams were small but that's not unusual. I love the Clam Box for the large bellies when available. Tartar sauce was just like JT Farnhams: pump your own, slightly sweet. Not my style. Around $19 with 2 sides. Rings OK. Fries actually really good, thick cut with skin on. They also have malt vinegar at every table.
Trip 2: The weekend special Maine Crab Roll. I used to love the old crab roll at Kelly's. This was even better (since Kelly's went to the horrible king crab roll with celery and chips as a side I've quit ordering it). Toasted bun piled high with tasty Maine crab. Mayo, nothing else. With fries $14.50.
Trip 3: Lobster roll and chowder. Very good lobster roll. Large chunks, small amount of mayo only. No lettuce, toasted bun. $15.50 with fries around $13 without. Chowder, similar to Kelly's. Not too thick. Lots of clams. I spy someone eating a 'naked' lobster roll with a side of drawn butter...trip 4. It was worth it.
Also of note - Ipswich Clambake is a great seafood store. I have been going to them for well over ten years (used to be on Route 1). They are my go-to for scallops, halibut, lobsters ... Their selection is usually small, but the quality is always great. They cook lobsters to order - call ahead and you can pick 'em right up.