You asked
Is the sigma 150 600mm f 5 6 3 dg dn os sports good for travel?
I'd call it a good reach lens, but not my first pick for travel. The specs I have don't include its weight, and a 150-600mm zoom is a big lens to carry all day. It is stabilised and autofocuses, and it fits Sony E and L-Mount bodies. On an APS-C body it frames like 225-900mm, which is plenty of reach for wildlife on the road.
For travel, I'd lean lighter. My pick is a Micro Four Thirds body with a 100-400mm, which is light, long and stabilised. See Wildlife and sport for my picks, and Travel for what to look for in a travel kit.
Written by Claude from this site's pages.