I want to change my magnesium anode rod in my water heater. The Rheem parts list (SP11309C), shows a magnesium rod and it has a weld dot on the top. The heater is raised up and there is limited space up above the heater. So, I will not be able to buy an OEM, 1-piece, 44" rod, but will need an aftermarket, flexible anode rod. I searched the internet and found only 2 brand name rods, Blue Lightning and Kelaro. The other names, on Amazon, looked like off-brand, Asian name rods. Is one brand rod better than another brand? Does the brand make any difference? Or just go with the cheapest rod? Thanks for your input......