LiPos don't like to stay fully charged (or discharged) for long. I have never tested how long they can take it - and honestly, other people telling me "it'll be fine, I do it all the time for X amount of time" are not reassuring to me either. Who says I'll be as lucky as them? And if I screw my batteries up, it's my money, not theirs.

So, personally I never charge more than an hour so in advance of using them (and mostly actually just before use) and I either put them to storage voltage while I'm still at the track before packing up my stuff (most of the time) or immediately after I get home (rarely), at the latest. Am I overly cautious? Maybe. But better safe than sorry, and I like to use and enjoy my batteries for a while. If you like buying new ones every couple of months, you don't need to worry as much. Still, always remember, be careless with LiPos and you may end up with your house on fire.

Ultimately you need to decide for yourself.