We simply state the fact that "your browser"
In fact my reaction was to scsi.
But only this simple statement, says far more then you might wish and by making such statement, you -are- participating in browser wars.
Fact is that the browser I use (being IE8) is still the most or 2nd most browser used in the world!!! And that's one of the several you are not accepting as should be. Which could give customers using the browser giving the feeling they are not accepted either.
I wonder how long you are in business (is it 2 years?) that you do not understand this.
I understand that you also block some poor others, wich also some customers are happy to use (unfortunately). But it's not your task to decide which browser customers should use. You're not in children garden, you're in business.
You can explect more professional company's to take that same opinion as I do. And you won't make money by referring to the competitors, which is also an arrogant thing to do. The "we do it like this, if you don't like it, go somewhere else" way of doing business is irritating more customers then you think (especially if company's are told their browser is no good). Customers mostly won't take this from a bigger company and especially not from a small company as yours seems to be.
But hey... it's your choice as you say.
And I'm entitled to the opinion that it's very unprofessional.
I hope you will see that some time. I have been there, done that... it's no good and won't bring anything (rather bring less). There are better ways.