Agree with everyone else. TB has a nice, crisp bite when hitting; whereas 4G just feels plastic and dull. Both are low-powered and stiff, but TB has some controllable power to it, while 4G just felt powerless and dead. 4G could be good if you need zero power and something that stays lifeless throughout. For some people it works, but personally I can't stray from TB.. it has all the spin and controlled power I need. Then the thinner gauges of TB just add some feel and pop to an already awesome string.
TB Soft is kind of a whole new string... totally different feel and power level, but definitely a comfy poly, although not quite as soft as Polystar Turbo which is the softest out there. TB 19 and TB 18 still had more crisp, controlled feel than TBS17