I've been running in Brooks shoes for almost a year now, and have used only the Pure Connect for all my training sessions. I have a neutral foot strike and I'm not too heavy, so I prefer using lightweight neutral shoes with minimal cushioning, with a heel-to-toe drop that is not too steep. Pure Connect delivers on all these requirements. It is the lightest in the Brooks PureProject series, but still has some good cushioning for my longer runs, and has a midsole drop of 4mm. My feet remained blister free on the times I used them without socks, thanks to the smooth fabric upper and nicely rounded heel. And unlike other lightweight shoes with low heel-to-toe drop that I've tried before, the Pure Connect also has substantial arch support.
I even used the Pure Connect 3 (below left) for Challenge Philippines early in the year, having first tried it just a couple of weeks before the race. And I used the Pure Connect 4 (below right) for the recent Ilocos Tri 113, with absolutely no break-in beforehand. Overall, it is an ideal training shoe for those who have a neutral strike and can get away with not much cushioning or support, like myself. But they can also be a great option as a racing shoe for those who prefer a little more cushioning than racing flats, and for those racing marathon distances or longer.
But for almost all of my races this 2014, I've used the Brooks T7 Racer. It's a minimal road racing shoe, coming in at 6.4 oz and in my favorite color - neon! :p I wear them with bungee laces for racing, but the original does come with this awesome orange set with silver stitching. I use them sockless everytime, and have had some issues with blisters on top of my foot, due to the stitching inside, especially when they're soaking wet from dousing myself at aid stations. But nothing that a few swipes of petroleum jelly inside the shoe couldn't handle.