i use a 2013 Macbook Pro at present, upgrading to a Macbook air later this year, personally with work I do/have done i have found the best laptop to be a Macbook Air as they are light weight and seem to have great battery life, I think battery life out weighs performance most of the time, I have my cracking rig back at the HQ hooked up to ngrock and hidden ssh online so i can tap into it from anywhere, even from my nexus phone sometimes, I have found it better to collect the hashes from the job and through them to the rig, then a little python script to through me back the cracked hashes when completed via either writing the file out and sending them to me on a reverse connection, or if its a big job a secure ftp server, on the Mac i have Kali running through VM, as i am more used to it over parrot, but when i get the new Macbook Air I will be installing it as the primary OS, as i have a desktop for gaming/media, but yeah my advice is aim for battery life over anything else, 4-8gb Ram and enough HDD space for everything you need really, my friend has an overpowered laptop with all the trimmings, but I have found i still work faster than him on my Mac as it just seems to run smoother somehow, but then again he is pushing his to the limits on every job, think hes kinda impatient haha, all this been said the only other thing i’d go for is a lonovo yoga as they have good battery life too, lastly all thats really required over this is a good WIFI card capable of monitor,
one last side note I also have an Rpi3 running kali which i have on a power bank in my bag for basic MITM work, and also ssh into that from my phone/laptop, but yeah hope this helps, I have tried many computers and setups but this is what works for me, take care Bex xx