What is a good size dick?
depends on what you want to use it for. 6.5 will not come close to satisfying the average female elephant nor will it win any long dong contests but when it comes to normal human sexual activity it shoud be fine as long as you know how to use it to pleasure yoru partner really well. And FYI, the average adult erection is just shy of 6 inches so if your’s isn’t doign the job then it is yoru technique not yrou size that’s at fault.