I use my 2008 HSE for towing, launching and recovering my boat. Could anyone help with two questions please?

1. Cobra do an A bar. Does it stop the front parking sensors working?

2. Watling Engineering make a front tow bar which makes it easier to see what you are doing with a boat on a slip. Does anyone have any experience of this product please? I asked LR if I would infringe the warranty if I fitted it. They replied that this was a "grey area"!

Many thanks

JGB