I sometimes buy the small packs of sushi in Tesco which I quite like.
How different are these from the stuff in a proper sushi restaurant?
I know freshness and price would be different but tastewise?

Supermarket sushi is notoriously mediocre at best, and sometimes outright bad. The stuff from even a moderate quality restaurant is much better, and the best restaurants are noticeably better than that.

It just is not a food that responds well to sitting around. Proper sushi rice starts drying up badly in 20 or 30 minutes or so, so they make it differently (and worse) for shelf life. Buffet sushi is bad too, for the same reason, but supermarket sushi is the worst. Also they always use inferior grade frozen fish and it's prepared crudely by someone who really doesn't know how to handle it. You will taste the different immediately.

If you like the supermarket kind, you'll love the real stuff. Though once you get accustomed you may find yourself too spoiled to enjoy the cheap kind as much.

As different as chalk and cheese. A sushi chef trains for years, it might be 5 years before they are even allowed to make the rice. If you go to a proper sushi restaurant then expect to pay a lot of money but get some of the freshest most amazing food you will ever try.

I've been invited to a sushi restaurant but don't really want to go for other reasons. So I'm not sure I can justify the cost. I'm not keen on going out for meals as I get stressed out and hot.
So just working out if it's worth the cost and anxiety.

I love cooked fish, I just can't get my head round the thought of eating raw fish.
I have seen Sushi in Waitrose and it does look nice but I am really not sure.

Sushi isn't necessarily raw fish.

Raw fish on its own is Sashimi. A lot of Sushi dishes contain either cooked fish, other meat entirely, or vegetables. Some use raw fish, but the most important part of Sushi is the rice.

Supermarket "to-go" Sushi is never made with raw fish anyway.

That is interesting, thank you

Was just about to say the same.
They put anything in nori rolls and similar these days, from hoisin duck to bbq pulled pork.

Sometimes it is here. It's just not very good raw fish, and even worse rice.

The stuff I buy from the supermarket never looks very much, but it is surprisingly filling.
I spread the wasabi on it all, cover them in soy sauce and scoff.

Tesco sushi doesn't even deserve to be called sushi. It's dry, salty and vile. It has about 2 days on the sell-by date - hardly fresh.

Do yourself a favour and go to a proper restaurant and treat yourself.

Even Yo Sushi! is a much better intro experience

Make your own at home. I've been doing it for years.

Well there's a surprise.

I've had sushi in a couple of places as well as from a supermarket. It is less fresh and cheaper but taste wise it isn't as nice as it would be made fresh.

I love sushi, but never had anything spectacular like over in the far east. I still enjoy it though and for a quick lunch would prefer a few packs of supermarket sushi, over a pack of sandwiches. I've tried pretty much all of the supermarket varieties and have found Co-op to be the nicest and Marks and Spencers to be very disappointing. The Co-op at the students union close to me actually sells premade sushi with raw fish, probably to cater to the large number of Oriental students. The supermarkets will tend to use smoked and cooked fish in their sushi.

Just had some from Morrison's. Quite nice with ginger, wasabi and soy. I don't have a sushi restaurant nearby so am quite happy with these.
Probably change my mind if and when I go to a sushi restaurant though. But for now....

I agree the M&S ones are disappointing, and actually quite expensive

You've just described 95% of M&S food.

I thought they'd be a bit higher quality than your average supermarket sushi, but it was actually one of the worst. Aldi sushi at about a third of the price is nicer.

It's possible to learn, yes, but surely it's a chicken and egg thing. They're not going to know what it's even supposed to taste like without having had proper sushi even one time before. They've gotta try it at a proper restaurant at some point. Then, if going out frequently is not practical for them, maybe learning to make it is the longer term solution.

When I've had it homemade it's usually comparable to the supermarket kind, and that's if they've had practice. It's deceptively simple. Just because there aren't many ingredients doesn't mean it's easy to do right. There is a reason that sushi chefs train for years to master it. There are lots of aspects of it that are actually tricky to get right, so a home cook will cut corners, leading to an underwhelming end result.

Ive been to many sushi restaurants in Japan and the sushi we get in the UK is pretty vile in comparison (particularly the Supermarket ones).

I would never buy it here in this country, its very different to having fresh sushi. They have more variety and ingredients in the Japan (and better skilled chefs). At least go to a high turnover restaurant they will have fresh ingredients.

Supermarket sushi salmon is smoked salmon as opposed to raw salmon. A high grade sashimi salmon (or other raw fish) is so yummy I could eat it everyday.

Used to live in Japan and go to the restaurants weekly and there is really no comparison to supermarket sushi.

Only type that Japanese would attempt to make at home is the California roll.
Even the cooling and the the vinegaring of the rice is a specialist technique over there, difficult to get right.

Couple of UK Jap restaurants where I go to to get sashimi but it's not as good as the ones next to Tskuji fish market.

Better to buy some local fish super-fresh fish here, cook it simply than any of the sushi boxes or YoSushi rubbish. Fresh mackerel end of month, barbie it on the beach or back garden etc.
Wouldn't go for the salmon anyway - it's all farmed unless you are paying top whack, so full of the worst chemicals, the least healthy choice of the lot.

Yes, completely different. I'll eat supermarket sushi now and then but it's really not comparable to freshly made stuff. Really recommend trying it