Yes... a friction sway is a must expecially on the single axel TTs. As far as the WDH goes, ona 1500 truck or rear leafspring truck you prob dont need one. We did out first year with the 165 without a WHD and our Envoy (which has a soft coil spring rear suspension) sat pretty low in the back with it hooked up and normal camping gear loaded up. I didnt like that and how it handled when going down the road (front end felt very light). Picked up a WDH thats prob overkill a bit for our 165 but I keep the links/hitch adjusted so there in minimal tension on the trailer and just enough to level out the truck. They make bars in diffrent classes depending on your TT weight so just have to select the right one for your setup. We're planning on going to a bigger TT so the WDH is moving over to the new TT. Never had any issues with it bending or damaging the trailer in all our travels. Oh..you will love that sway bar the first time a 18 wheeler passes you on on the highway! Feel free to PM me for any specifics.
*Currently trailer-less but shopping
07' GMC Envoy w/ P2 controller (current TV)
88' Chevy K5 Blazer (soon-to-be TV)
74' VW Superbeetle (1303)