Best watch as a tough workhorse?

[Ruud Van Driver]

Having been a very happy Rolex owner for a mahoosive four months now, the thought of going off on a travel job without a Rolex and wearing my trusty old Citizen instead gives me the creeping geebies. I'm now considering picking up a pre-owned, older piece for travel jobs. I can wind up in some very ropey places as well as some extremely pleasant ones. My watch can sometimes take a bashing while crawling through ballast tanks, cofferdams, cargo holds etc.

My question is, what would be a good choice as a solid, robust workhorse? I'd be looking for the best compromise of value-for-money, tough as old boots and relatively discreet. I'm guessing non-date sub?

Many thanks in advance