The first negative always hurts, but don't get too tied up in it. Feedback was originally conceived back in the 'good old days' when everyone ran auctions. Today it is becoming less relevant.

On both our accounts we are lucky to receive feedback from 1 in 20 sales. Buyers don't care any more, they just want their stuff.

We have now stopped giving out feedback all together as it's a waste of time. The only benefit of the feature is for buyers when they want to vent their spleen when something goes wrong.

Customers will still buy from you if you have over 95% I reckon. eBay is a discount store and people just want the cheapest price.