I'm assuming that you're talking saloon here?
If not, I have the Avant and I seriously wouldn't worry about the boot space, the main difference is that the boot floor is about an inch or so higher than the non-hybrid version which does cause a small lip but nothing to worry about it's still massive, you just lose a bit of headroom.
The rear seats also don't fold flat with the boot and have a similar lip between the seat back and the boot floor. I'd take some pics but it's currently stacked full of PA equipment! 😆
If you are talking saloon, then all of the above is of no help whatsoever (but might help others) & hopefully someone else can answer your query.