I would always use an angled jack into the bass, be the socket on the front or side, straight jacks can make a mess of your bass if you forget and put the bass down on to the jack, far less protrusion with the angled jack makes for less damage if you do plonk the bass down on the jack. Most of my decent cables are of this configuration ...
...I also use the silent angled jack because I tend to forget to turn my amp down before I unplug and it saves the inevitable boom!