I have it on my Velar. It's a repeat purchase for me because I also had it on my previous Jaguar F-Pace.
It works perfectly on the Velar. I love it. When I play football, badminton or go skiing I no longer need to worry about keys falling out of pockets or, if left hanging in a jacket on the touch line, someone pinching them and driving off with my car.
On the Jaguar they could be retrofitted by the dealer but that costs more than choosing it at the outset as an option. Activity Bands from other cars won't work. They are unique to your car only and cannot be reprogrammed.
I was told it couldn't be retrofitted by the dealer, but I suspect it probably can, they said the loom needs to be made up for it. Anyway I ordered one thinking it was a bit of a waste, however after some thought I think it's the best extra I added.
I have a Leisure Activity key - didnt use it at first but when i did use it once, quickly realised it is quite good.
My car has it as standard but you can have one retro-fitted - costs about £500
Dealer will fit a transmitter in the rear door near the Land Rover badge (£250) and you buy the actual key (£250) which needs to be paired to the transmitter and car.
Not sure if it is the same key across models.