Old man!!!
Mind you, I am 50 next Saturday.
I'm definitely a tubeless set up fan, especially as many of my rides take me through forest gorse, and or bridleways that have hawthorn and black thorn hedges. I also got fed up of fixing punctures at 10.00pm on cold, rainy winter nights.
The last time that I removed a tyre that had been running a tubeless set up, the inside was riddled with needle sharp thorns. This time there was non, but the carcass of the Hutchinson tyres is very tough.
I didn't have any luck with Stans fluid, and found that it formed into small rubber lie balls, after just a few months of use. Others have found no problem with it though.
The only reason that the Caffelatex failed to seal the side wall hole, was because I had been putting off adding fluid to the existing set up, as I knew that I was going to be swapping the tyres around.
I'd imagine that most decent off road bikes, comes fitted with wheel sets that are tubeless compatible/ tubeless ready. The same for tyres, but check first.
The valve core looks the same because it basically is, but is fitted in much the same way as a valve core is to a car.
You can fit the kit yourself, but my advice would be to ask the bike shop to fit the kit prior to you taking delivery of the bike. It isn't that it is any problem, but they will have experience of fitting the kits, and you don't won't be playing around with things like that as soon as you get the bike.