My primary need for a laptop is mobility and runtime as well as decent quality / reliability - and I find that Sony's flagships usually satisfy this requirement. In the last two years I've probably bought close to 30 upper-end, Made-in-Japan Vaio's - mostly duplicates to put in the various workplaces I occupy. And of them, I believe three have needed attention, two for a very minor issue. I've liked the understated styling of the SZ and TZ ranges. I'm not finding the new TT and Z machines as appealing, although they are better machines as such.
The crapware can be removed, but you can't add the Vaio attributes to another lesser machine which may not come with crapware. With any new Vaio I just spend a couple of hours figuring out what I should get rid of, do a base install of my own apps and I take an Acronis dump of that state.
The three-in-thirty ratio contrasts sharply with the 80-plus-percent FOA/minor/major repair rate of Apple notebooks I've purchased in the same timeframe (91% this year). And since the Vaio's offer better runtime and portability, they have actually been carried around more than the Apples during the same time. As I was saying elsewhere, I have no idea how good or bad Sony's support is on a regular basis, because I hardly ever need it. On the other hand, I have a very good idea how Applecare is, because I need it so often.
I think Lenovo is overrated these days, although they still make fine notebooks - it's just that Dell's upper-end business range / Sony's upper-end range nudges the quality of Lenovo's finest, and this isn't so much as these two manufacturers radically raising it's standards as Lenovo's dropping slightly over time (I think the matt cases hid this for a long time). The last Lenovo I had was the X300 - nothing has really caught my eye since then.
Dell is who I turn to for the mainstream. I usually buy only from Dell's Latitude and Precision ranges with minor exceptions. I currently have a small brace of M6400 Covet's, which are probably the best 17-inch-class semiportable machines I've ever used, packing extreme power into a not-too-extreme weight, while being visually rather appealing. The Studio notebooks were purchased for a virtually throwaway task, but turned out to be unexpectedly good for the very low price and I'm very happy with them. The XPS's were more of a mixed bag. The 1730 and the 1710 before it, I've found to be solid machines if spectacularly ugly (and weighty). The M1330 on the other hand has been a disaster of almost Apple proportions - and I think I was even more apoplectic at Dell's XPS support because although I've grown to expect utterly crap QC and chronic lack of reliability from Apple, it's not something I'd pegged Dell with before - at least, not on a non-budget machine like the XPS series. The latest XPS - an XPS 16 - we'll see. So far, no issues and it's a solid machine.
Between Dell and HP, Dell tends to get the nod more often from me as their account manager offers better deals and I also get better benefits of a large business account, including sneak peeks at new stuff. However I do have a few HP mobile workstations and I can't say anything bad about them - very solid machines, well engineered if not as visually salubrious as the Apples or even today's Dells.