I think i can contribute here since i had the Hammers in 12 oz and the Shield in 14 oz. Had Sabas Pro Series, Rival, Fighting, Cleto Reyes and now Winning. The Hammers in 12 oz are a very good bag glove. Feedback like a cleto, but the amount of more protection you get is on point. Sparring is a no go with them, at least in 12 or even 14 oz i would say. The Shield is like a pro version of the giant 3.0 (not 2.0). Better Materials, better stitching, better designed, better padding, but softer. Its a really soft glove much more soft than a winning, not everyone likes that.. in 14 oz its a very safe sparring glove, even for heavier weights, or if you go out with more power.
In my opinion the downside for both of these gloves, and i think this concerns also the giant 2.0, is that venum havent changed much about the design. This transitions into the feel when you use this gloves. They dont have anything "special", just good standard gloves like their cheaper series with better materials and finish, but with the same bad design. So in conclusion, if you consider the pricepoint they offer, you can do yourself a favor and just go with winning.