Boot time doesn't really matter much. When you see people on YouTube getting really fast boots, they go in and configure the computer to do that specific operation very well by disabling things that you would likely use in a normal scenario.
Do things like search for files in indexed folders (e.g. My Documents). They should appear almost instantly if the drive is working right. You can also try duplicating a 2-4 GB folder to the same location to see whether you are getting more than 300 MB/s or so. If you copy a large single file, such as an HD movie, from one 850 EVO to another 850 EVO, then you should get closer to 500 MB/s.
Another option is to use the Samsung Magician software to optimize your drive and then test its performance. Here is a link to the latest version - 4.6 - as of today (it will automatically start downloading from Samsung's Website):
http://ssd.samsungsemi.com/ecomobile/ssd/update1.do?fname=/Samsung_Magician_Setup_v46.zip
As someone above said, be sure to enable Rapid Mode. Also, you can set your Over Provisioning to 20%, which will ensure your drive won't slow down much as you use it while also keeping the drive snappy and responsive.
If you really just want to focus on booting your computer over and over again, rather than actually using your computer, you'll need to tweak your BIOS. Enable "Fast Boot," "EUFI boot," turn off your motherboard's post screen (the thing that prompts you at the beginning to press Del of F2 to enter BIOS), disable all RAID arrays, use AHCI mode, and connect to a SATA 3.0 plug routed to your chipset rather than you AsMedia controller hub (check motherboard manual for which plug goes where). You'll also need to mess with Windows to do minimal boots. Basically, disable all startup programs, and turn off all services that aren't required for operation (i.e. almost everything). To even have a shot at super fast booting, though, you must have installed Windows as UEFI (not legacy). Here's how to check whether you installed it one way or the other:
http://www.eightforums.com/tutorials/29504-bios-mode-see-if-windows-boot-uefi-legacy-mode.html
Doing all that will take you a lot of time. You'll Google what everything is, one by one, and then you'll finally get your 10 sec boot. But it will costs you hours and hours of screwing around. You'll also boot into a minimally functional computer. I'd recommend, if you go through with tweaking Windows, to take note of all your previous settings so that you can restore Windows back the way it was. Leaving it like that will cause weird errors that are hard to diagnose.
As for the BIOS, you can keep most of what I mentioned above without problems. The only exception is that you may have to switch from AHCI to RAID if you setup a RAID array, and you'll want to re-enable the post screen to more easily get into BIOS (unless you never enter it anyway).
Good luck!