I've owned a Kvetun feder for a while, and just finished ordering a sidsword from them. The feder is excellent; very durable, very nimble, and sturdy-feeling. I've also handled one of their Easton sabers. It's not mine, so I can't comment on the durability, but it looks great and feels good in the hand.
The reason I'm writing the review, though, is to echo what others have said about their excellent customer service. I wanted to swap out a part from one of their rapiers onto one of their sideswords, something that required a fair bit of discussion as to what combination would best fit what I was looking for. I spent the whole time worried that I was getting on their nerves, but once I confirmed my order, they actually THANKED me for asking so many questions. In their words, "it is always nice to speak with a fencer who knows what he wants." They really put in the effort to understand what their customers (and, by extension, the HEMA community) want.