Also bear in mind that unless the FMS has dual GPS update, the FMS position may be drifting as you lose multiple DME inputs to keep NAV accuracy high. We do circling approaches in an LPC/OPC but it is really to highlight the traps you can fall into and it is very much a training exercise.
Our sims have good wrap round visuals, but as the original poster says, you still can't see behind the window like you would on a real visual circuit or circling approach.