For the brightest blades and most "realistic" effects (like scrolling ignition and localized flash-on-clash), look for Neopixel sabers. These have LED strips inside the blade.
Star Wars The Black Series Yoda Force FX Elite ... - Amazon.com Amazon.com lightsaber buy amazon
: Offers a massive range of sound fonts and visual effects, combining a classic design with modern tech. For the brightest blades and most "realistic" effects