Hello,
There are many views on this one within MZRC, I have owned an etz251lux and the saxon tour 301. The saxon handles,runs,smoothly and is very forgiving, when misused in all weathers, and ridden in hooligan or touring mode. Tyre and set-up choice is the key.
Best of the MZ electrics, brakes, instruments, and available touring kit on the market,and plenty of spare parts, new or sec/h, I have full Krauser frames,top-box and panniers on my one, with Michelin tyres. Rebuilds engine/frame all straight forward and only need one special tool, the clutch puller, as for the others Hot air gun to 900c variable and a freezer (bag, the parts or dead man walking) 12 rebuilds, 120K miles later, works for me.
Saxon fun is the same except for the frame mounted fairing and bigger fuel tank.
Overall, both models are good, but finding a good looked after one, is the big problem, Good fortune with your choice