And I still have a toshiba satellite from 2008 that works as well as the day I bought it. I think reliability isn't something only high end manufacturers offer.
And my 2011 Dell I use for networking has only gotten better with time. Larger battery, more ram, SSD hd, Blueray DVD RW.
I will take something that can be updated over something that is just a few mm smaller any day.
Still using a 2011 MBA. I just had to change out the magsafe charging port/IO board, but other than that its held up great.
Rocking a (very abused, still working great) 2012 MBA and a 2012 27" iMac. Only changes were a new battery (€70) and more RAM.
I still use a late 2009 MacBook Pro on a daily basis and I have absolutely no need to replace it. It's fast enough to browse the web, watch videos and do light programming work. I've only replaced the hdd with a 128GB SSD few years ago and everything else is stock and still works.