sens are smaller then endli's? Yes.
what size to endli's get to? Captive bred anywhere from 20-30", Wild caught about 30-36", expect about 28".
sens are 12"? Some might get there might not.
price wise typically is there any difference in them? Here in the "states" you can find senes for about $8, endlis anywhere from $40-75.
personailty wise? Endlis are one of the more laid back types that just lay around the bottom and senes are considered to have the most personality constantlly swimming all over the tank.
feeding wise? They eat the same. Majority of wild caught specimens are found to have a stomach full of talapia. I feed mine raw shrimp, cut tilapia fillets and Hikari Massivore Delight sinking pellets.
or if you have any info on my other options let me know.