I use NIS, have for a number of years. Generally a good product and I dont have any performance issues but patch rollouts have been very buggy. It is one of the few to support encryption on Excel, and the identity safe feature is great.
But I am not a fan of the Norton 360 etc because they try to 'manage' your PC.
**if** you are just running NIS, firstly make sure you have run liveupdate to ensure you are on the latest version. The most likely cause of any sluggishness is a 'background scan'. You *must* let the laptop complete a full background scan, the best way to do this is to just leave it on an untouched for a couple of hours.
