If you thought great sushi meant a long-haul flight, Mayfair would like a word. Two of London's most interesting sushi counters sit within a few minutes of each other around Park Lane and Berkeley Square, and they take very different approaches to the same craft.

Sushi Kanesaka, tucked behind an unmarked door inside the 45 Park Lane hotel, is the intimate one. The omakase room seats just four or ten diners per sitting, with the service running about 90 minutes and Shinji Kanesaka himself leading the kitchen. The menu moves fast through highlights like chutoro, a yuzu-dusted seabass nigiri and a silken chawanmushi with scallop and crab, but the sleeper hit is the simmered sweet octopus – reportedly massaged for half an hour before marinating, which explains a lot. Sparkling sake flows throughout, and the tiny room means you'll likely end up chatting with your neighbours.

NIJŪ, on the corner of Berkeley Square, goes for something warmer and more relaxed. Culinary director Endo Kazutoshi calls the style "katei ryori" – home-cooked dining – and the oak counters and amber lighting back that up. The accessible entry point is the nine-piece nigiri selection at £62 a head, which in Mayfair is genuinely reasonable. Chef David Bury talks diners through the procession: Portuguese snacker-light snapper with shiso flowers, Korean flounder with yuzu, seared Japanese red bream, and a chalkstream trout with roe in dashi-vinegar jelly. The dry-aged tuna flight is the centrepiece, finishing with a nine-day aged collar served with caviar. Save space, or skip dessert entirely and head downstairs to Nipperkin, the cocktail bar styled like a 1950s Japanese listening bar.

For travellers, these two make a strong case for a food-focused London trip. They're the kind of bookings you'll want to lock in ahead of arrival – the Kanesaka room seats just 14 people a night across its two sittings – and both pair naturally with an evening around Mayfair, whether that's post-dinner drinks on Mount Street or a browse through the galleries around Cork Street. If the budget stretches only to one splurge, Kanesaka is the theatre-and-precision experience, while NIJŪ delivers top-drawer fish at a friendlier price point with a bar to extend the evening.

Neither is a casual lunch stop, but both reward the booking: this is counter seating at its best, where watching the chefs work is half the meal.