Apart from $dayjob MBP, all my laptops/servers run Linux. So Linux compatibility is a must. Things which don't work should be unimportant to me (fingerprint reader). I use Linux Mint, as I don't want to be messing around with my primary machine, and everything just works with it. Best Linux desktop experience I've had in 18 years of running Linux desktops.
I opted for Sager/Clevo platform because of research, reviews, etc. I'll talk Dell, HP, and Toshiba below (which I've also owned).
Clevo platforms are mostly end user upgradable and servicable, so if you need more of something, with a screwdriver and some patience, you can add it. This probably doesn't make sense for the people whom are concerned about damaging their machines, though as someone whom has built machines for ~30 years now, this is old hat to me.
My 2010 model has 16GB ram, i7 quad core, NVidia GTX 560m , and now a SATA SSD, along with a PCI gigabit ethernet port, some sort of intel wifi card. It was showing its age, in that the GPU (on an MXM card) was starting to fail under load. I replaced CPU/GPU fans, cleaned the unit, though failure events are increasing, and the gigabit occasionally isn't recognized on boot.
Add to that this it runs hot and loud. The fans are always on, and slightly more than a whisper during idle. During heavy load, it can be loud. Not ideal for my situation. No usable effective battery life, call it about an hour if I am lucky. Screen resolution is 1920x1080 or something. I had plugged it into an old monitor on my desk (recently replaced with a HiBP 3.8k x 2.xk) and it ran 1920x1200 nicely.
It is heavy. And the battery clips don't keep the battery secure in the machine. So there's that.
I looked again in great depth at the options. Here is where I talk about my Dell experiences.
Every single Dell laptop I have ever bought, every single one, has had the infamous "unknown power supply" bug, which has only been curable by a motherboard replacement. These were high end workstations (4100), mid range consumer, and cheap consumer units.
The take-away. I cannot and will not recommend Dell. I will actively recommend against Dell. Their build quality generally sucks. Their ability to survive more than a year before needing a motherboard replacement is lacking. Their cases and keyboards are a bad joke. They are bulky, annoying, and not serviceable by mere mortals.
Linux sort of/kind of works on Dells. Not really, but hey, they market a ubuntu laptop.
HP has generally been reasonable, usually offering some insanely interesting combinations of things at good prices, but then making other choices on the same platform which require you hack crap hard to make the thing work. I loved my big HP laptop. I hated that it used a NIC that only had windows drivers. This was back in the PCMCIA days, and I was able to find workable pcmcia NICs and modems (yeah, really dating myself there ...).
I bought my wife and daughter Toshiba units one year to replace their failed Dells. Toshiba failed within 9 months of acquisition. Not serviceable, and Toshiba wouldn't honor its warranty. So, out to the dumpster with those.
We bought a pair of Samsung laptops to replace those. Nice specs but cheap plastic case, and both eventually died with chassis fractures.
By this time, I had had it with windows (7 pro) and its insanely broken networking. I gave them a choice on their next laptops: either Macs or Linux machines, as I was refusing to support windows any more. They played with my work MBP (linux at home on my laptop, MBP for work) and linux box. Chose MBP.
Cost me a bit more, but it just works (as do the linux boxen). Nearing the end of life for these units, and they are looking at new ones in a few months.
Short of it is, for their work, mostly editing, web stuff, etc. MBP is fine. Similar to SW dev in many ways (and daughter is getting into SW dev in college), so this works out well.
For heavy computation, analysis, visualization, my new unit is quite nice.
Sager NP8156. I upgraded from 16GB to 48GB ram (I run lots of VMs), and upgraded the WD 250GB SSD to 1.5TB of SSD. NVidia GTX 1060 with 6GB ram. USB C and USB3, integrated PCIe based NICs, good wireless. Easy to service. Runs linux mint 18.3 on a 3.8k x 2.x k monitor at high res. Even under load, it is quite quiet.
Downsides: 1) I didn't opt for the higher end display on the laptop itself. 2) Battery life isn't great (2 hours).
I brought it with me on a business trip to Korea a few weeks ago, for some of my dev/testing work, alongside my $dayjob MBP with emojibar (can't stand that thing). Better overall experience. I used it as a NAT/router for the team there with me, while running on it myself.
What would make it better would be a better screen res and a better battery. Otherwise, for me, its a perfect workstation replacement unit.