I went the "build your own" route. I already had a Spektrum transmitter and wasn't really impressed with the prebuilt offerings. I went with a ShenDrones Tweaker 180 for the frame and mostly RMRC electronics (ESC, vTX, motors, flight controller). The benefit of building your own is that you know how everything works. Also, if you break something, the parts are relatively east to get. In my case RMRC and GetFPV can deliver parts to me in 2 - 3 days. You also have more freedom to mix and match parts.
With that said, there are a few drawbacks. If it is your first build you there will be a lot of trial and error testing. I burnt up a couple of parts, found out that my initial receiver selection wasn't ideal and my vTX placement made it prone to damage. You can work around most of those issues by following a build that someone else has done for the same frame you choose. The one thing you cannot learn by watching reviews or reading articles is soldering. Good soldering skills are a requirement for doing your own build. My soldering skills started off below average and now I would say they are good enough. Lastly, the final drawback is cost. You are looking at $300 - $400 just for the drone if you use quality parts (RMRC, Tiger, Lumineer, etc). If you don't have wire or a soldering iron you are in it for even more. Goggles are also $200+.
Building your own drone is very rewarding, but it can be frustrating, time consuming and expensive.