In a domestic kitchen yes, but isn't this just something that's useful and convenient in a busy restaurant kitchen being marketed to domestic cooks because every other potential user's already got one?
No not at all. Domestic Sous Vide machines (both the sous vide supreme and the new Lakeland machine) operate via convection accurate to a steady temp of around 0.5F whereas most commercial machines are water circulators accurate to 0.1F Dittto the domestic vacuum suction machines (limited to dry ingredients) vs the commercial chamber sealers which can seal down liquids also.
The domestic kit brings the professional technique to the amateur not the professional equipment.
I'm a Masterchef standard home cook (if i were 28 rather than 58, I'd be on the programme) and Sous vide has enormously expanded my repertoire and improved the quality and consistency of my cooking. That's not to say that SV is only for gourmet cooking - I have a number of things pre packed and ready to cook in the freezer. I can arrive home from a ride at 5pm, fire up the SV, fill with hot water, drop in the bag. Then clean the bike, have a shower chill with a beer and have a great meal ready for 7pm with minimal effort.
Oh and i forgot: homemade SV limoncello in 3 hours start to finish is to die for. the machine is worth it just for that!