Just make sure the chip can be read by universal scanners.
Some companies encode the chips or use frequencies that cannot be read by universal scanners, which does NOT help if your dog ends up at a shelter with a different kind/brand of scanner.
"Smitty" GSD (rescue) ~ Happy goober dog
"Ilda" WGSL 4/28/10 ~ Wild Thing
"Autumn" Australian Shepherd 10/9/11 ~ Fluff Ball