Disc's vs Digital

I'm looking to get a new PS4 and start buying games but I've never boughten digital. I love the fact it lives on the device and I can't scratch a digital copy but can anyone weigh on on the pros vs cons of both and what you go with. Also, rules for digital say I want to get SWBF2 and I get it on my ps4 and I end up getting a new ps4 can I re download or how does that work. THanks