PK Deli in Cambridge. Hole-in-the-wall, gargantuan subs, solid quality (esp. pastrami), approx. $10 and definitely passes the crucial test of: "I can get two meals out of this, but I want to just finish it now and spend the whole afternoon out of commission in a food coma".

Cafe Rustica: Down the street from P&K, not huge, but tasty and decently-sized and in the $10-12 range.

Roust: maybe. Took over the Mt. Auburn Darwin's. Kept a lot of things the same, though TBD if they can hold the candle to the former sandwhich kingpin's quality. The price is also borderline...

I mostly list Roust bc I was a former Darwinian and they are the most logical Successor Sandwich to the fallen great.