I have the PC3, All I can say it has come in handy more than once, I use it to move my trailer full of Kettle Korn equipment around in tight spots at fairs, It is one of the best investments I ever made.
I found mine used on EBAY, It works as advertised and maybe even better, I real bad about over doing it with it but never had any issues.
Once you get the hang of it you can pretty much pivot the trailer where ever you want, They have a adapter you attach to your trailer I would suggest you get with it, I don't have it but I have multiple jacks on mine so I normally just use main trailer jack as my pivot point.
2009 Georgie Boy CruiseMaster UFO
Donald E. Ethredge