Usually I look at all the different options and judge them on their merits - but if I had to jump-in to buy some new parts with no prior knowledge then based on previous experience and reputation I would pick the following:
Monitors: Dell - I've had many Dell monitors, they have all been great and the warranty service is excellent
SSD: Crucial (though intel would be a close second) - they are fast, reliable and good value
PSU: Corsair - they use a lot of different OEMs for their supplies (including Seasonic and CWT) and they pretty much always come up with units that are great quality, good value and covered by a good warranty
Motherboard: Gigabyte (though MSI is a close second) - nice quality components, good features and good warranty service
Memory: Corsair - This one is less of a strong one - since other brands are great too - but corsair's kits do look nice and their warranty is good
CPU cooler: Thermalright - My first one was a TRUE, I installed a TRad GPU cooler and recently used a silver arrow, all have been great quality and provided excellent cooling
Graphics card: Gigabyte - Same reasons as the motherboard
Headphones: Sennheiser - Excellent sound quality, and they are built to last
Mouse: Logitech - Great quality mice, comfortable to use and logitechs customer service are fantastic
CPU: Intel - based on their performance the last few generations)