I had my MOT today. Got a Sabelt wheel.
Upon collecting he said did it not come with a steering wheel airbag as standard, I said no it did, I've changed the wheel.
He said you'll have a problem next year then, as it'll be a fail.
Something about only if you've got a specific type of Harness..
Regarding seats my Recaros are using standard belts + pretensioners, so all should be fine there.
Don't know if that's just his interpretation of the ruling..