I have been using the shield for many years. I have tried many putters before, and I have tried many putters after.

I still like to switch things up for fun. But as for the shield. It's definitely one of my favorite Go-To putters. Especially inside 40 ft. 
it really isn't that fast. But not slow. It's not that glidey. But it's not a brick. It's not that overstable. But it holds a nice overstability for a long time. 
overall I'd call it 2.5/2.5/0/1.5. 
conpared to other 3/3/01 and 2/3/01 type putters. It really fits almost in between. 
it's perfect for putts and the plastic is the best. I've been playing for 16 years. And trilogy baseline. Especially the medium flex is my absolute favorite. 
I don't even use much trilogy in general. But the putter plastic is my favorite. 

I have been playing for over 15 years and have switched my go to putter several times, from the magnet to the old school aviar, to the dynamic warden, the judge, and a few others and finally 2 years ago i found my perfect putter..the westside shield. the softer bt plastics get warped to quickly and the bt hard isnt quite soft enough or grippy enough in the hand. The bt medium burst plastic is the perfect combination of durability and grip. I can hammer this putter pretty hard and it goes straight for ever. it is the most perfect putter for any advanced to professional player in my opinion.