My son is looking for a full suspension mountain bike. Something with a modern geometry and 27.5 tires. Medium size is what he currently rides but I am thinking that large may fit him too if I install a dropper post. His budget is $1200 but I may extend his budget by a couple of hundred bucks for the right deal. We prefer slightly used lower or medium grade bike over used $4K bike that has seen a lot of miles. He is spending all his saved money so there is going to be nothing left for upgrades/fixes.