The real answer is that it depends. if a dealer is hurting for money and has to make payroll, rent etc. cash (or check) is available immediately. Getting financed can take days or weeks to get funded and something as little as not having proof of insurance can hold it up. Ask the dealer that you are working with and they will tell you if it makes a difference. Asking us does nothing since we are not the dealer selling you the car. Everybody is different.
2009 Lotus Elise White
2008 Nissan Titan--2002 MBZ S430
2008 Aprilia Tuono--2010 Harley Road King
2008 Aprilia RXV 550/KX 250
Tons of mountain bikes