It's important that you build the right type of rapport with VCs.  However, it's hard for many first time entrepreneurs to figure out what type of relationship they should have with VCs.  Should you be deferential, bossy or a cold professional?

The answer is 'none of the above'.  It's a bad idea to be too defferential or to be overly complimentary.  Those tactics are transparent, seem calculated and ultimately make people uncomfortable.  Similarly, being bossy will offend VCs and being cold will make you a less desirable person to work with.

Ideally your relationship with a VC should be that of a partner.  Treat the VCs how you would treat a respected business partner.  Be polite, friendly and responsive.  This doesn't mean that you shouldn't challenge their assumptions and engage in debate - just do so as you would with a business partner.  You should also get to know them.  Building the relationship a little beyond the business world will make working together easier in the future.

At the end of the day the compatiblity of your team is a factor in the investment decision.  The best way to be compatible is to be is treat VCs like a future partner