Me personally I would use exactly same method. One, this method never fails. Two, I've never used the blasting method which is known as good, but is it good enough on greasy/oil build up which is also super hard on the valve heads?!
I would worry about setting it all up to find out you still have to do what i did.
If blasting can do exact same job then I assume it's a quicker method, but how about the plates, would they still have to be done by hand?
By hand you have a better control as well as think and seeing it all coming off and looking better and shinier with each move of your hand is just a pure "engine p@rn satisfaction".
There probably isn't the easy answer for many, i just know I would use the same method.

An old post I am resurrecting here. But a common issue on the S8 nonetheless. Collapsed swirls flaps that is. Rather than take the flaps out of the intake and risk losing some drivability (or having to remap to compensate for taking them out), I went for what I saw as a quicker and easier solution that I can do myself. That being take out the old and put new in its place.
Symptoms being a rough idle, a mis fire code on cylinder one and eventually engine management light on. All this within 48hrs before I took it off the road. It did also then finally register a code with the swirl flaps which confirmed what the problem was. I did not fancy driving it anywhere like this. So with some guidance from here and elsewhere I took the job on myself. I did find a piece of swirl flap in cylinder one! Hence the mis fire. And bits of plastic flaps loose in the intake. I think back, I was getting an irregular intake noise under part throttle load about 2 weeks prior.
I suspect Pierburg make this part of VAG. Since the original had exactly the same Pierburg part number on it (7.01116.08.0). I sourced the new intake from Germany on eBay for £1180 delivered. The new part comes with a new throttle body gasket but you have to swap out the alloy piece on the top that takes the two water coolant pipes. So remember to do that before disposing of the old part.
Whilst in there. It made sense to do a manual carbon clean. Albeit walnut blasted less than 25k miles ago. I did sheer a bolt by overtightening the throttle body but it came out easily and I got a replacement from our sponsors easily. Not an easy, quick or cheap DIY job but a lot cheaper to do yourself. It's done now at least..
Two rear parking brake motors at the same time. They had been on their way out with intermittent faults for some time and getting gradually worse. Here it seemed to be a choice of a Chinese or OEM version. With a huge price difference between the two. I went with TRW’s. I don’t know if they make the OEM version - but felt it a safe bet. All good now for another 175k miles. At least these parts.
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Good job! I did read somewhere of this Pierburg replacement, might have seen it on AutoDoc can't remember. Shame no one does just the flaps but still that manifold is a lot cheaper than one from Audi!

Just over £3,000 for the manifold from Audi, I remember enquiring for mine

Prior to me buying the S8 in February '18, the previous owner had got the manifold replaced around the 100k mark. Cost him £2,500.

Current price is £3193 incl VAT

I guess no decoke option in that price. But does it include fitting or just the part itself?

That's just the part :eek2: