Comment 7 for bug 1458014

[ 15.940712] vboxdrv: Successfully loaded version 4.3.10_Ubuntu (interface 0x001a0007).
[ 14.431291] vboxdrv: Successfully loaded version 4.3.10_Ubuntu (interface 0x001a0007).

Drawing conclusions from only two tests may be asking for trouble, but it looks like you've experienced 1.5 seconds of difference in the first few seconds of the system's boot. This large of a difference seems worth investigating further. If you've got the time and inclination, please generate some detailed bootcharts: https://wiki.ubuntu.com/BootCharting

Thanks