ImperialBlether - I do think he's wasting a hell of a lot of money and I think you seem a bit blinded by admiration for him.
What on earth gives you a right to say he is wasting a hell of a lot of money, Imperial. Just because he is spending lavishly, doesn't mean he is wasting it. Do you know his exact incomings and outgoings, I don't think so, I would doubt even the Op and her ex do. So how can anyone say whether he is wasting money? He has told Op he is also saving well, what is he supposed to do, save all his earnings and not spend?
A nice flat, car, holidays, are not wasted if you can afford them, they are just living to your means. Similarly with nice clothes, wearing expensive clothes may be part of the image required by his well paid job. £800 for a bottle of wine - extravagant to most of us, but not wasted if he can easily afford it and likes to collect wine. People spend a lot more on collected items, and cars/holidays, without being able to afford them.
I was admonished by a friend not long ago because my dH and I had the audacity to waste our money buying our DS a car when he passed his test. Primarily for practical reasons, so he could get to his part-time job, but the reason is actually no ones business. We can afford it, we have good earnings and a very high 6 figure amount in savings, plus pension provision, yet my friend didn't think we should spend our money as we pleased!! Yet I never tell her how to spend her money?
Gingernaut - since Op doesnt mention a partner, why does he need a will, or insurance at 28? The latter is only really needed if he has dependants, and whilst a will makes life ewsier, His parents would be next of kin if he died intestate!
Op - I don't think you are blinded by admiration, I think you realise that your DS's spending is none of your business, nor is it any business of your ex's or his DM's. Just cut them off every time they call.