To my eyes, it's just a cheaper made Browning AB3 since FN owns them both. Action is identical, with slightly different contours. The barrel is attached with a Savage style nut, and there is no recoil lug washer, just a notch that beds to a molded into the stock steel bar. The trigger is more adjustable on the Winny, but the mags are all plastic and hold one less round then the AB3.
I have a pair of AB3 and have no complaints with it, nice and light and accurate. I'm sure the Winny version is fine, just made a bit cheaper.