Hi Eva
So long as you are prepared for every outcome, it may go well or not, what ever you decide to do you have to accept the situation.
It is never nice to deceive your SO and the freedom you get from letting the cat out of the bag is fantastic, but once the cats out you can't put it back.
It also may be a positive outcome at first but this can change and you may need to adapt your dressing regime to accommodate your SO's response.
Good luck