    Sentence 1: We were offered a term sheet  by a VC group, but the terms gave them  the option to invest (or not) all the way  lout to April (it's November) at the  current valuation--is this unusual?    Sentence 2: We have a signed term sheet  from a VC that grants them exclusivity.  However we've had a serious offer from  another company for an outright sale -  what's the right thing to do?