What brand of computer should you be using?
A number of years ago, Apple ran their famous Mac versus PC ad. Truth be told, it was one of my favorite ads of all time. It hit home on the competitve nature between Mac and PC users.
Fast forward to today, it seems that the differences between running Mac or Windows are mostly cosmetic to the average user. Most applications now run on both systems and do so quite well. For most, they can focus on where the price and specifications provide the best value.
That said, the question still comes up, especially among new designers starting out. While I say that it doesn't matter as much, it does come down to which system has the best user experience. As designers, we all know how important that is.
Something I will add: tablets are starting to make more noise in the market. Capping off 2018, Adobe announced that a full version of Photoshop will be coming to the iPad. I can't say I'm surprised by the move. Affinity Designer and Photo already had their apps ported over as more designers shift towards using tablets.
At the moment, tablets are still a little way off from the power of using a full computer. I suspect this will change in the next few years and am excited to see the day when it happens. What's so enticing to me about tablets is the ability to draw. Using the Apple Pencil is great because you can get that sketchy or organic feel that drawing shapes in Photoshop or Illustrator doesn't get you.
Getting past all of that, price is still a major factor for almost everyone when it comes time to buy. Macs are known for being pricier than a PC when you compare then spec to spec. While it does feel great to buy the newest, greatest, or fastest, I'm not sure it matters as much anymore. Unless you're doing super-intensive work, there's a lot of reasonable options with slightly less horsepower. I've personally had great luck buying refurbished and clearance computers towards the end of the year. Apple does a great job keeping a list of this on their website. You have to keep an eye out, but good deals pop up from time to time. The most recent MacBook Pro that I'm on right now actually got for a fairly decent price compared to the new version of it. The nice part about it, is it still comes with Apple Care. I get that peace of mind that if anything goes wrong, I'm still covered. It's a good deal, especially if you're not a student (and you can't get a student discount).
Truth be told, I don't have much experience buying PCs anymore. But I do recall from when I did way back in the day that they had similar promotions for students and refurbished options as well. For the most part, Adobe works just fine on slightly slower machines.
You may find on the PC side that you don't need to buy a computer with the specs maxed out right away. If you're handy with electronics, it's pretty easy these days to swap out things like RAM or hard drives. It helps financially, as you're able to spread out the investment that you're putting into your computer over time.
My last point: if you're afraid that people will judge you for using a computer that may not be hip or cool, find a good case, get a bunch of stickers and sticker up the back of the computer until you can't see the logo on it anymore. No one will probably be any of the wiser.