While we are all debating "seconds" per day, some food for thought...
A watch nearly always leaves the factory well regulated - anything can happen in travel (temp deviations, watch gets bumped around etc etc) which can all have an effect on a watches timing.
While I'm sure you could send it into IWC to be regulated, don't be surprised if it comes back running worse off, or dust is under the crystal, or a new scratch on the dial etc - all sorts of things happen when a watch is opened up - all over a couple seconds a day.
I once sent a JLC Navy Seals in for adjustment as it was running -8 a day (clearly not good) - JLC sent it back to me saying it was running within spec and they knocked the indicator on the bezel at 12 loose on me. Now the irony is, the watch came back running spot on and JLC didn't even open up the case.
If you dig around on forums, you'll find countless stories of watches coming back worse than they went in.
Is +10 ideal? Probably not... Is it worth losing your watch for potentially a month or two only to have it come back worse off? It's likely it'll come back running within +7 a day, but really is it worth the headache? I guess only you can decide :)