One thing to remember is the factory voltage regulator is a SHUNT to ground so any amparage the Stator is putting out that is not used will be shunted to ground so saving power for gas mileage WILL NOT HAPPEN.
But if you do the alternator mod and get rid of the stator, good to go. Doing this so you can add more accessories or lights then it too is a good thing to do.
A few years ago I bought two
RED 1157 LED's and two 1156 Amber LED's from SuperBrightLED.com
The RED are MUCH brighter. They have like 48 LED chip and about 1/3 are taillight and 2/3's are brake lights. I can see road signs light up behind me in the dark real well.
The Ambers also have 48 chips and will flash real fast without an LED rated flasher unit like
Slabghost said above. But I mounted them in my scooters front turnsignals in the mirror housings that are normally DARK when riding and wired in a SPDT 5 pin relay to cycle them OFF when the wire has voltage for the blink. So they are off faze with the rear turnsignals. For the rear turnsignals I replaced the 5W21's (1157) with 2357's as they are not on all the time.
I can post the wiring diagram for the SPDT relays if someone wants to make their front turnsignals into running lights. You will need two of the 5 pin type (87a)