I think my cat is allergic to his plastic Brake-Fast bowl

Boy I cant win with this cat, the drama just keeps going on. Okay he has had this brake fast bowl since November 10th to keep him from vomiting from eating too fast. The last week he has be scratching under his chin and around his face alot, no bleeding or scabs and mostly during and after eating. I see nothing, no black residue yet from the oil or bateria that could be on the plastic. I passed on the metal bowl as amazon reviews blasted it for metal flaking off and cheap quality.

So now I have to decide to keep the bowl and just be alot more vigilant cleaning it four times a day and hope for the best or get rid of it, go back to a human dish and hope he does not start vomiting as even tiny amounts of soft food on a flat dish had him vomiting.

Here is one made in Stainless Steel.
Dura-pet Slow-feed bowl
But I am curious though... Are you feeding him something new? Anything at all? This does sound strange... I am not sure if this contact would be enough for this reaction - it sounds to me more likely to be food allergy than to the dish itself. If it was to the dish, IMO you would see something like acne spots or something...
I don't know, this is strange...
But anyways, I do think a SS dish would be a good idea regardless

I'd definitely look into a stainless steel bowl and get away from the plastic ones. You can also use glass or ceramic.

I got a speed bump bowl for Tex who is a scarf-n-barf. It's heavy, hard plastic. Been using it a couple of weeks and so far (knock wood), no vomiting.

But I am keeping a lookout for chin acne. BTW - I only use it with his wet meals 2x/day... because gobbling wet was the problem.