The Freebit odds are based on what people here bet would win so it can end up biased, think thats correct where as some sites are relying on an outside system. Its nice when you can get the advantage of good odds on what you would bet anyway but not here where your favorite is too popular. Sometimes I have used this to hedge, a sidebet to add to my other bet elsewhere depends how you like to play.
Ah, I didn't know WoF spins from FUN could be accumulated. Long time user here but only since yesterday I bought up some FUN, and might keep adding more if the price keeps spiralling down.
I'd definitely hang on to spins and put them in a go if I thought BTC would crash, although also keeping them all in and using them at once for higher lottery chances is legit (coupled with a high wagering session maybe).