I have that Magpul SL handguard on my sport along with threir short vertical grip. I think its great. Easy install, very affordable and a far more comfortable grip. I would use one again.
Minor upgrades:
-Strike industries Viper handguard
-FAB defense grip (feels excellent)
-Nikon buckmasters ii 3-9x40 (just got it this week, didn't zero it in yet)
-Nikon p series mounts. Wish I got a QR mount system though.
-Plano 42" case