Those are both great bikes. That Yammy will run like a Timex. The TS is much more tame than the TM and rides like a 4 stroke. Long, broad power. You should keep them both.
I've got a '71 Yamaha 250 and a '73 TS 400 for vintage riding. Just got the TS because my buddy got one a while back and loves it. Although I've not ridden the TS much, I can tell already that I'm really going to like it.
BTW, your TS is a '72 but has '73 tank emblems. ('72 are silver background with black letters and '73 are black background with white letters). Other than that, yours looks really original and you got a great buy. I need a set of emblems for my '73, so if you decide to change them out, let me know. I'll buy your '73 emblems.
Have fun. Vintage bikes are a blast and have the best smiles per dollar ratio of anything on the planet. My buddy with the TS and I are going to do a vintage Baja trip in a few months. I'll put images on my blog link below. (I'm an idiot with technology, so you need to scroll down the get to the photos.)