In regards to bullets not being seen when you use them against Jedi...Jedi have the Force, they can sense it coming. It doesn't matter. 😛
Not to mention the sound of the gunshot, if you're trying to be stealthy about it. If it's loud, anyone can pick it up and find you. If you've got a silencer, I'm sure a Jedi could find a way to find you...
Blaster, hands down. Taking in the fact that in Battlefront, the sniper weapon is a laser, and that gun shoots almost the speed of light. This shows that lasers can really move as fast as they want, or as fast as the manufacturer chooses. If you look at a laser as a lightsaber without the hilt moving, then it is only limited by whatever makes it move forward (the propulsion). The argument that a Jedi can feel a bullet or blaster coming is completely wrong. Anyone that has been through the KOTOR series can tell you that. Sith Assassins would use melee and blasters to take down Jedi before the Jedi could sense them.
Taking in all this information, Blaster completely outweighs a gun.