I decided to install Linux Mint (which is heavily Ubuntu-based) directly on my old A1260 MacBook Pro in 2015 - I ran into some interesting quirks with the GPU (had to force it into BIOS mode) but other than that, I ran the machine for a year purely on Linux. After setting the machine up how I liked it (I really like the Cinnamon UI, even though it's much more Windows-like), I moved the same configs to my other machines. I have a ThinkPad X220 also running Mint with an extra battery for traveling, and a seldom-used desktop PC.

The aging MBP finally wore out in 2016 and no longer powers on (but after 5 years of daily use, I'm quite impressed with it). I bought a custom-built Clevo gaming laptop from Scan's 3XS division, since it gave me a lot of say over the hardware - I chose Intel and nVidia where possible to ensure compatibility. I intended from the start for the laptop to run Mint, and it has done so impressively - it has a 1TB SATA SSD for the OS (which I have dual-booting Windows for games) and a second 256GB NVMe SSD dedicated to my Steam library. I like that the machine has enough RAM (16GB) that I can casually jump into a Steam game whenever I feel like it without closing what I've currently got open, and that the RAM and SSDs are upgradable. It's also covered in ports either side, including ethernet and 4 USB3.0 ports. And it cost me less than half that of an entry-level MBP.

I found Linux is mostly there, but there are some things that Apple still does much better. The touchpad is the most obvious - even using a utility like Fusuma, multi-touch is still only fluent on a Mac, and the Synaptics pad on the Clevo often takes several swipes to register. The keyboard is also nowhere near as nice - I have to press the keys very hard, and often use it with an external. The UI, however, is extremely usable and familiar, so much so that I've converted family members using it. The hardware support is excellent - all the hardware, Wifi, USB ports etc. worked out of the box - and the performance is superb. I spec'd a good i7 chip for future-proofing and it's still extremely fast, and the Geforce graphics handle 3D gaming with ease.

One major hardware problem I had was that the screen cable wore out after only a year of use, and although it was replaced under warranty, it seemed like a very silly thing to wear out so soon. For comparison, the only hardware problems I experienced on the MBP were a detached Bluetooth antenna (probably from when the previous owner upgraded the HDD) which just clipped back on, and the webcam cable failed, but I was able to buy a spare and replace it myself. I also kept the machine very clean and was surprised at how little dust there was inside it. The bottom panel of the Clevo comes off easily enough, but the fan vents seem much more inviting to let dust into the chassis. Battery life is also abysmal - with the machine set on the nVidia GPU, it lasts less than an hour, and less than 2 days in sleep mode. I didn't buy it to use on battery, however, as I regularly travel between fixed locations so I have mains power.

The longevity of the MBP did surprise me - I used it daily for 5 years with no problems, and went from Snow Leopard (which is my all-time favourite OS) up to Mavericks. The build quality was very, very good, and with the exception of Lenovo ThinkPads, I can't think of another machine I could expect that much useful life out of. However, Macs are no longer upgradeable and are very difficult to repair - current machines have the RAM soldered to the board, and if the SSDs are replaceable, they're proprietary Apple ones. I made it a goal with the replacement to have it upgradeable - the CPU will address up to 64GB RAM so I would be able to quadruple the factory value when 32GB DIMMs hit the market (they seem to be close), and the SSDs are standard. I added the second one 6 months after I bought it. That said, the case does not feel anywhere near as solid and rugged as the MBP's metal chassis - I took the MBP around the world with me, but the Clevo feels a lot more fragile, so I take the ThinkPad instead now. I looked at the T-series ThinkPads but none of them had offboard GPUs when I was shopping.

Don't forget, with Linux, you can easily try before you buy - download an ISO, write it to a USB stick and boot your current Mac from it, then check out the OS from the live environment. Try a number of different Ubuntu variants, e.g. Gnome, MATE, Kubuntu, Xubuntu etc., see which GUI you get on best with. For hardware, I would definitely recommend ThinkPads.