I never considered soldering copper that big a deal. But I have very little experience. Maybe done 50 joints.
None ever failed. Hate plumbing but too cheap to hire a plumber for simple stuff like that.
Clean both surfaces, flux, apply heat, place solder on opposite side of heat, watch solder suck in, wipe, done.
None of us can answer your question as one error in judgement does not make someone stupid. Beware of those who say it is your money and spend it as you wish. Very true....but it a nice way of saying...not a good investment. Enablers tend to support eachother. On the side, your friends may just be envious. YOU KNOW THE ANSWER