OR RNs in my system make more across all levels (clin 1, clin 2, clin 3, clin 4) than our floor, ICU and ED counterparts (and those groups make more than clinic nursing staff). We have three OR settings through - we have a surgery center, a community hospital and a trauma center - each of those is different, with the trauma center pay rates being highest. It's a significant difference of several dollars per hour over our counterparts in any other setting.
In addition to a higher base rate, we are paid our system's standard evening, night and weekend differentials. We are paid to be on call, even though we might be sitting at home (currently 10% of our hourly wage, so someone making $30/hr would get $3/hour on call). If we're called in, we get travel time plus I think two hours or guaranteed pay just for clocking in - even if we're sent home 10 minutes later.
There are some negatives though. Like not being able to really leave to get lunch, a snack or run to the bathroom without being relieved by someone else (unlike the floor where I could keep an eye on your patients so you can grab lunch). If they're calling you in overnight or on the weekend there may not be staff to get people out for breaks (or you might get forgotten by accident). It can also be a really bad time to get lunch or a break in your case and you may not be able to leave. If there are "too many" rooms running when you are scheduled to leave, you can't just leave...you have to wait to be relieved.
In my facility - floor, ICU and ED RNs (and nursing staff - NAs, CSTs, etc) are capped at 60 hours of work per 7 day period. Any guesses who that doesn't apply to? Periop, specifically the OR. I've had more than a few weeks where I've worked or been on call 7/7 days in a week. I've had horrible weeks at work and then been on call the following three or four days of a holiday weekend. I've worked 25+ hours in a 30 hour period.