You can see the look on the house sound op already? Frankly, they wont care as long as you give them the audio on the right connector. They’ll shrug and accept what you give them, but they will hate it, and tell everyone the sound wasn’t them.
The thing we all hate is a pre mixed, eq’d and effects laden source we cant control. Reverb and delays are worst, because the audience hear your mix, plus the effect the room has on it. So many venue have rotten acoustics, that a wet mix can be a train wreck. In a rehearsal space you turn up the treatment, but in a bigger room it could just be a swampy mess, and they cannot fix it. Id at the least speak to their operator and get their opinion. You are forcing them to just take your mix, good or bad. At the very least, give them the option of the clean mic. The other thing is monitoring, where do the band get your voice from? When you rehearse using your split system, they probably get your voice direct, and through spill from your setup, on stage, wont you have more monitoring level to balance against the house system. If they are relying on hearing you through the PA, it might be nasty? Are your reverb and delay settings really complex? Could their mixer not replicate it? I have had my sound op really upset by bands with bizarre systems. Me asking why it sounds so awful, and him saying its not his fault, its what he's being sent. Just be careful here. If you can provide them with a signal on an xlr, they'll get it into the system. They might accidentallly not have a DI box if you offer them anything else, as an excuse.