This might tip you back the other way, but I'll write it anyway
The 'cord is the superior built camera, and with the Tessar clone on the later III, IV and V models, it gets reasonably close to a 'flex for a fraction of the cost. They are well built (significantly better than the Mat), but they suit slower shooting - the levers are clunky for fast shooting.
The Mat has a brighter screen, faster to operate (and I reckon slightly better to focus) but with lower build quality.
Don't think about a Rolleiflex until you are deadly serious about TLRs. If you do, I recommend a meterless 3.5E. If you are in the TLR world you'll have a separate meter anyway, and the E seems to have lower prices despite being very similar to the F (and same lens designs). Planar or Xenotar doesn't matter, although we tend to have more Planars on the market in the UK.