Well, hydro is faster, but I don't think its that much faster. I think it may be faster by a week or two compared to soil if done right. In hydro you have all the controls, that is oxygen and nutrients. You don't have that with soil. I also think for example a plant in hydro using media such as the clay pellets and others, such as perlite offer less resistance than soil, and so they grow faster and mature faster.
Another difference could also be when your friend says his is ready to chop it may not have his triches at the same stage yours would be when you harvest yours.

keylime