No 20, Sanctum Soho Hotel, 20 Warwick Street, London W1

Sanctum has been billed as London's first rock'n'roll hotel – a Soho pleasure-den where touring bands can kick back and enjoy some discreet fun, and even us civilians can feel like rock stars for the night. So what's this – a morning phone call asking me to call back and confirm my dinner reservation? Not very rock'n'roll, is it? Don't try and pin me down, man; who knows what wild antics might have derailed me by 8.30pm tonight?

Mind you, the babysitter's booked, so yup, I'll be there. Early press reports claiming that Iron Maiden were backers of Sanctum proved disappointingly inaccurate. But there is a connection with the creators of (Room) Number of the Beast. The band's manager is a partner in the business, behind the substantial figure of the ebullient Mark Fuller, whose other ventures include designer chippie Geales and West End nightclubs Sugar Reef and Embassy.

Carved from a pair of Soho townhouses once occupied by MI5, Sanctum is a boutique hotel with a whiff of Jack Daniels about it; alongside the private cinema, roof garden and "funky crash pads", there are muso-friendly touches like the availability of guitars and amps on the room-service menu. The ground-floor restaurant, No 20, is open to all, though I took the precaution of including in my entourage a genuine pop star, who had a number one hit in 1986 (even though he has since become a vicar).

The smallish dining room makes a valiant stab at high-style retro glamour, without quite pulling it off – Mika rather than Bryan Ferry. Chairs are upholstered in red crocodile skin and semi-circular banquettes in rose-gold leather reflect a flattering golden light. My guests all looked like slightly more attractive versions of themselves, as though someone had retouched their artwork.

Unsure of what to expect from a rock'n'roll menu, we were pleasantly surprised by the unshowy modern- British fare on offer. There's plenty for the road-crew as well as the headline act, with dishes like macaroni cheese, pork chop with scrumpy jus, and fish pie. More high-maintenance offerings include Wagyu burger with foie gras, and ''rare-breed omelette with fine herbs'' (£10.50), a piece of nonsense which could have come straight from the rider of a particularly demanding pop diva.

A starter of pink grapefruit, quinoa, pomegranate and avocado looked gorgeous, like a carb-free take on jewelled rice, and the nicely tart dressing turned the flavour-dials all the way up to 11. Also good was crab and sweetcorn chowder – bisque-based rather than a classic chowder – which came with brown crab meat on toast. Potted shrimps suffered from a higher than acceptable butter-to-shrimp ratio, but the sweet undertow of mace was appreciated by the ex-pop star, who somehow managed to survive the 1980s with a fully functioning olfactory system.

The Wagyu burger – made from the lead singer of the cattle world (fed on beer and massaged daily) – was definitely a cut above, with a moist, open texture and good char-grilled surface. But the accompanying skinny fries tasted frozen, even if they may not have been. Spit-roast Goosnargh chicken and Longhorn rib-eye steak were both decent bits of meat, properly prepared, and pan-fried sea bream on cauliflower cream with Dublin Bay prawns was a really well-executed dish, if pricey at £24.95.

The food was better than we expected, but by the end of the evening, there was no escaping the fact that we were on our own in a near-empty hotel dining room. No rock stars, no magnums of Cristal being cracked open, and only the soundtrack of Nineties-style chill-out music to ease the come-down. In fact there is something about Sanctum, with its diamanté door handles and rooftop hot-tub, that feels like it has missed its time, in a way that the Soho House and its offshoots never do. "It's like a hotel owned by U2, but down a few chart positions," was the verdict of the ex-pop star.

With a steamed lemon pudding from an old-school list, our bill came to around £45 a head, including a 2008 Craggy Range Avery Sauvignon Blanc (£38) from New Zealand. Not cheap, certainly, but OK considering that some £10m was apparently spent on opening Sanctum.

The hotel may well earn its place on the itineraries of touring bands, but the restaurant will probably attract a slightly different clientele; civilians who want a flavour of life in the VIP area. Remember the old joke – what do you call someone who hangs around with musicians? (Answer: a drummer.) No 20, decent food notwithstanding, raises a similar question. What do you call a restaurant that hangs around in a rock'n'roll hotel? Answer: I don't know – but I probably won't be going back to find out.

Food
Ambience
Service

Around £45 a head, including wine and service

No 20, Sanctum Soho Hotel, 20 Warwick Street, London W1 (020-7292 6100)