We use ShipHawk and NetSuite WMS, not sure what you mean by NetSuite ESP, thinking you meant ERP? There are both a lot of Pros and Cons, but the Cons are being worked on by ShipHawk. Pros would be it does integrate somewhat nicely with NetSuite, a few hiccups but overall decent. The Rules engine in ShipHawk is decent, now that they finally got the ability to use "And" and "Ors", when we first onboarded with them, they only had And as on option in the Rules. ShipHawk has caused us some major headaches, like on go live, the deleted all of the rules we had set up, but they did get them restored. The biggest Con I can think of, is that their BOL's and Shipping Labels are not very easily customizable.