I buy from smaller manufacturers, without an installed O/S. I consider what equipement is in it as my main criteria, next to price. Keyboard & touchpad are also looked at carefully, & preferably tried, using live distro(s).

Oh yes, I made a pretty big mistake there. So yes I trust more manufacturers who provide GNU/Linux support, and use components with free (ideally) or open source drivers.

My Latitude is still chugging along and I've got another one coming so I guess I've made my decision.

I like both Dell and HP business laptops. I've had several Latitudes (C640, D600, D610, D630x2, E5500 x2, E6520, E5430 and now E5450) never had major issues with other than a bad motherboard on the E5430 that was replaced under warranty (wouldn't allow you to upgrade firmware), and while started using them much more recently, I've had a couple Elitebooks (8460p x2, 8470p) and they have worked quite well also what little I've used them.

I trust my two recently acquired refurbished Lenovo Thinkpads, since I removed Windows. Don't know if there's anything lurking in the BIOS or HDD controller, though. So adjust trust to 98, maybe.
EDIT
Strange, but when I typed the per cent sign, it appeared in the edit box, but not when I posted/saved.
"&)(
Nope, not there.
%%
WTF??? Still not appearing after 98 above.
98% 98%
**** it.

Different machine:
adjust trust to 98, maybe.
Nope. What's going on?????

My way to buy a computer is to look for a manufacturer whose hardware quality has got value for money, i.e. it must run several years without it's parts getting failed and it's going to trash.

Second I do not want to buy a computer with softwares pre installed, as it also adds up to it's cost and I do not use Windows.

98%

No idea, shows up when I type it.

Yeah, it shows up if it's typed on its own:
98
but not as part of that phrase I used:
adjust trust to 98, maybe.
What??? The is there now! But not when typed on its own.
Weird.
98% 98% 98%
50%
1%
23% of people understand percentages, the other 69% don't.

I've had the best results with Dell Latitude, just had to do a warranty claim on my son's venue tablet so we'll see how good their customer service is.

Two truths are that I had a similar situation where I had a clear warranty return with Dell. The laptop was brand new, they sent a replacement one along with a label for returning the original. Semantics were that the replacement came overnight or next day and the other one just went into that same shipping box with their label, same sort of return situation, overnight or next day. So it was cool because they didn't punish you by making you wait or double charge your credit card, etc. They just took care of business. The other part of it was, Windows/Software install or configuration problem, I forget but I felt it was something which could've been resolved. Zero reason why exchange should've been necessary. Their tech support was all "Press the ON button", "Is the computer plugged in?", "What do you see on the screen?" it took several hours and they really couldn't help us so they did the exchange and I believe with some competency they probably could've solved our problem and not done that whole exchange. I do get it; the product should've worked out of the box, less hassle to just send the customer a new one versus debug what's wrong with this one and then get the failed one back re-image it, and move on. Problem is if they fix it with the several hour long tech support call, that's one thing, but they still have to go through that process to conclude "exchange" and that works, but you're frustrated by that time.

I still have this old Dell Inspiron 6400 lying around in a drawer. It must be > 10 years old now and it still runs. It tends to overheat and clocks down quite a bit, but I guess that could be fixed by opening it and cleaning the ventilation... Really amazing. Back then I could still get the install CDs for another < 20 Euros or so to wipe it and do a clean Windows XP install.

Arrf, good old times. The whole factory reset partition and no install media logic they came up with really sucks. Don't know how I'd cope with it if I was still using Windows...

My strategy was to hope nothing bad happened as my whole system slowed to a crawl.
Actually... hoping nothing bad happened pretty much comprised my backup plan as well.

It's not perfect, but a rsync command on a crontab entry does wonders

Glad I don't deal with that lurking paranoia anymore (don't fail on me..)

My experience is:

+ Asus X54C (i3, 4GB ram) - best experience ever. All the hardware easly recognized with Slackware 14.1 and also with Ubuntu (don't remember wich version... maybe the 12.x)
+ Other Asus - generally works quite well

- Compaq 615 - Bought because shipped with no operating system so I've assumed GNU/Linux friendly: it was a tragedy! Slackware worked quite well (13.37 if I remember) but hardware needed firmware installation and software configuration. Even ubuntu needed some extra configuration (if I remember, disabling the ACPI) to run the installer but next worked quite well.

So I'm quite loyal to ASUS laptops