I was wondering, whether such a setup works okay when it's raining? Because I'm afraid water may get between the tent walls and bed sides and as a result one can end up sleeping in a puddle lol
I don't have personal experience with this but plenty when it comes to tent camping.
If rain is a concern a simple rain fly will alleviate it.
Big tarp a couple ties and your concerns should be gone.
__________________
After all is said and done, more is said than done.