If you have a modern van with ESP etc, go for a dedicated electric kit as it will enable any trailer sway protection/stability control.
I fitted a standard bypass relay on the old one which involved a fair bit of wiring, new one was much easier, just plugged it in and strapped the cable.
Also means if you have a decent socket set and torque wrench (I have a Aldi special) you can save about £150 by fitting it all yourself, mine probably took 90 minutes last week.
My old towbar was a cheap PF Jones job, all the powdercoating flaked off and went rusty, so this time I paid £20 extra for a Witter one that is properly painted.