IMHO, the difference is in the learning curves required to use each product. MS is a "simple" tool which allows most traders to view a chart and make some computations on which they are going to base their decisions. TS is a lot more powerful, but the price is that it is also much more complicated to use and has many "features" that if not fully understood, can result in large losses or unpredictable results from trading.
If just starting out in trading and programming, KISS (keep it simple) is a mantra worth considering.
BTW: there are other platforms too, not just MS and TS, each with their own capabilities and limitations and costs.
$0.02
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