If you want to travel from YPR to SBC, or vice versa with luggage or to change over of trains, then atleast once check the trains runing. Pretty ample amount of trains run between these two major terminal stations of bangalore. Auto and bus are also good available but still they are costly and time consuming (considering the bangalore heavy traffics). Also its very cheap. General ticket costs just Rs10 whereas prepaid auto would cost 7-8 times higher.