Same here. They are great to dela with and we have never had a problem. SOmetimes it can take up to 6 weeks to arrive mind you. But that is the postal system not the seller. It can usually take anything from 6 days to three weeks as a norm.
At less than half the price it is well worth the wait though.
Don't forget if you order from the US Customs might get hold of it when it comes into the UK and charge you VAT, plus an import charge plus the courier company will probably stick you with a handling charge too... It still works out cheaper but not quite as cheap as it first appears.
I used to buy from here too but note that the dosage is double what you give in the UK as the product is only half the strength. I think there may also be a question as to weather it is legal for competition over here too? NOt 100% sure on the second part but I seem to remember this coming up before.
I have also gone through them myself and there have been many posts about this in the past, I did however also contact Equine America and it was they who told me about the strength difference. Even the measurse you receive with the US version are much larger and therefore would tend to support the fact that it is not so strong; as I said I'm not 100% sure about the "competition legal" aspect but I just have a feeling that I was told that in the past too
But horses for courses, whatever suits your horse best