Both the Yamaha Aerox 155 and Hero Xoom 160 are rather uncomfortable scooters owing to their stiff rear suspension and, in the case of the Aerox, a thin seat and cramped ergonomics for taller riders. 

Since your monthly usage isn't all that high, you could use these scooters and live with them, especially if the roads in your city are, by and large, well-made. It won't be a very pleasant experience if you don't have smooth roads. 

Plus, venturing out on longer trips with these will be even more tiresome as road conditions on Indian highways keep fluctuating. And neither is great at pillion comfort either. 

We recommend you instead take a look at the TVS Ntorq 150. It promises similar performance, with far more comfort, while coming in at a lower price point.