Reversing camera aftermarket

[StJohn]

due to a life/limb threatening RTC last June (not my fault!) I found myself having to consider Motability options and where every I looked I always came back to Volvo and in particular the V40 D4 Nav R-Design Geartronic, I REALLY wanted a Mercedes as I was in an e-class when the RTC happened and the Emergency Services said it saved my life. Sadly, those on offer are just not up to the normal Merc quality and ride standards. And as Safety is now paramount to me the V40 just made sense. The local Volvo dealer came up with an offer for the car above and he had one in stock, but a lot of features that I'd of liked couldn't be fitted. It's brand new and I took delivery today. It's a very awkward situ as I'm still receiving treatment So my better half will be driving for the moment but I've had a left accelerator pedal fitted so it can be driven both normal and left footed if needed, I had a really good deal with a 25% reduction in the partial payment.
However, I want to fit an aftermarket reversing camera and have found many online that are wireless Bluetooth, some have an interior mirror that contains the screen, others have an independent screen and some connect via traditional cables. I can even get ones that have an iPhone app for Bluetooth connectivity. some cameras fit to the number plate and others in the bumper or the boot lid.
The problem is I cannot find any info as to connecting to the Sensus Connect touch and as I can play dvd its clear the reversing screen is still available and it's my understanding that as soon as you engage reverse the screen becomes active but doesn't display as no cam is fitted.
So, I throw myself at your mercy and vast array of knowledge, should I pursue using the in built screen or use either a separate monitor or the iPhone option. I believe the yellow and red pin plugs are ready to use as a connection point but i'd prefer wireless. please help