As long as you get name brand gear, the specific brand doesn’t matter much. Patagonia, Northface, Mountain Hardwear, REI, Arcteryx, Marmot, etc. all make high quality clothing. The brand you pick is up to you and your personal preference. 

The most important items in your gear bag are: 1) waterproof gear, 2) boots and 3) sleeping bag. Don’t skimp on these.