http://ark.intel.com/compare/91167,88192
Above link shows the difference between max CPU in the nTB vs the max in the TB - both 13". Turbo frequency is 200 mhz in favor of the touchbar model. Ram is 2133 vs 1866 which in real world would only be noticed with benchmarks - similar to 200 mhz clock increase.
The GPU is virtually identical according to various benchmark sites, of course the 550 is faster than the 540 but not by much. 5% - 10% depending on application- similar to the CPU. (Geekbench shows 4000 for ntb vs 4400 for 13 max tb model).
Now if your argument is - but but on prolonged stress tests etc the 13 touchbar has more head room due to 28W TDP and won't throttle. Yes you're right. It will finish the job faster, slightly. If you really need a fast machine, the 13" is the wrong device, regardless of touchbar or not.
If you're the average joe who just likes a fast and responsive machine, with a complete keyboard and no gimmicks, the 13ntb is hard to neglect - especially due to discount offers available.