First Bike Build: Kit or Homemade?

Hello everyone. I'm new to this community and looking to make my first build. (Apologies beforehand if I am not abiding by forum etiquette). I'm very interested in learning how to build a motorbike as I think it will be a fun project that I can learn from. My question is, what 4 stroke kit is the best for the money? Money isn't particularly an issue but I'd prefer to spend under $400. I don't want a piece of junk I need to fix every weekend. I was looking at ThatsDax Titan 50cc kit and wondering if this would be a good starter project or if it would be better to build one from the ground up buying all the individual parts. Much Thanks. All replies are greatly appreciated. ~SpeedRacer