As tempting as it is to buy from across the pond, it can often be very expensive and troublesome to do so. I don't know anything about the specific kilt maker/retailer you mentioned, but Chas and Rocky bring up very important points. What you think you're paying isn't necessarily what you'll have to actually pay to get your kilt. Shipping from the UK is absurdly expensive, and customs can be a real problem. If they hit you with fees, they will hold your kilt hostage until you pony up the money. And when that happens, you'll wish you had just bought one made domestically. This isn't to say that it will happen, but it can and does happen all the time, with no rhyme or reason. Random people get their kilts hit with import duties, which can add quite a bit of cost. Best thing to do is just factor that possibility into your actual cost so you won't be surprised later. You can only be relieved if it doesn't happen, not disappointed when it does.

You seem happy with the $300 mark on a 5-yard wool kilt. Why not consider a USA Kilts 5-yard wool kilt? The price is $320, and you can talk directly to the guy who is responsible for making it (or overseeing its quality in his shop). In fact, you're already talking to him in this thread! You won't have to worry about overseas shipping or import duties or delays in customs. And he has an excellent reputation amongst this group (including myself) who have done business with him.

So in the end, you'll likely get your kilt faster, at the same price (or perhaps less), and you can rest assured on the quality of craftsmanship. If it were me in your position, it would be a no-brainer decision to buy from Rocky. I know that doesn't answer your original question, but it should at least hopefully give you something to consider.