I have one in inventory and wondered the same...I see people asking for Achilles or that Ancile shield. I also got a Venomhusk shield to drop that looks good.
It's a great shield but I can see how the ancile is better. Shield recovery. That makes a big difference when it comes to just how useful that shield actually is. It may be much more important after the next big patch too. I think the gate shield is better than achilles though.