No, they're exactly the same. Well, almost. The weave is the same and the fabric itself is the same. The only difference between the two is that Etaproof made garments come factory finished with a very tough flourocarbon based treatment used to shed water. Talbot products, as far as I can tell, are not finished in this method. Personally, I'm against proofing Ventile. I've tried it and found the results somewhat disappointing. The whole purpose behind Ventile is to allow the individual fibres to swell (which is why they're often known as 'Balloon Fabrics') and when chemically treated, I personally think that this diminishes the fabrics inherent water shedding abilities.
I hope this helps.
Cheers,
Adam
