Most all-you-can-eat sushi joints either limit your options to the point that you're forced to order extras, or serve fish so foul the deal should be renamed all-you-can-not-vomit. Get an honest and delicious deal at Midori.
Midori's a raw fish mini-chain with three locations spaced out conveniently along Ventura Blvd -- all date-friendly, unless your uncontrollable gluttony makes even The Ivy a harrowing experience for your female companions. The three Midoris serve endless, high-quality sushi with no catch: after 3pm, their entire menu becomes a $24.95 gorgeapalooza. Want Hawaiian King Mackerel? Damn straight. Hamachi? Hamach-yeah. A Sunset roll, w/ Tuna, Salmon, Shrimp, Masago, and spicy mayo? 'Til your own rolls double in number. Even appetizers (vegetable gyoza, salmon skin salad, etc) are included, allowing you to all-you-can-eat you all-you-can-eat -- an infinity-squared that will tear the fabric of your pants/the universe.
As a bonus, everybody gets a free Uni, and there are only four extras: deep fried shrimp head, Yellowtail Belly, Albacore Belly, and Quail Egg -- but at only a buck or two more, your only limitation will be the grinding march of your metabolism.