Most Beijing subways until recently were all loops, so you could get there via subway, but it would take a long time because it was a giant loop rather than being direct. They are top notch, I'm glad other people take them, but I'll take a taxi unless I need to get somewhere during rush hour.
Especially getting to Beijing South in the morning with luggage, a taxi or hiring a car via didi is the best way to go. To get to Beijing south, how many transfers do you need to drag your luggage through? So let's see, from where I used to live with the lines in place now: I would need to drag my luggage to Tuanjiehu on line 10, take the loop around to jiaomenxi, and then take the line 4 up to beijing south. Or I could pay 50 kuai for a taxi from my apartment complex gate to the front door of the train station.
Especially getting to Beijing South in the morning with luggage, a taxi or hiring a car via didi is the best way to go. To get to Beijing south, how many transfers do you need to drag your luggage through? So let's see, from where I used to live with the lines in place now: I would need to drag my luggage to Tuanjiehu on line 10, take the loop around to jiaomenxi, and then take the line 4 up to beijing south. Or I could pay 50 kuai for a taxi from my apartment complex gate to the front door of the train station.