GPS
Currently thinking about going with the MAX-M10S-00B. Going to use an external antenna. Sparkfun wrote a library for it. slightly more expensive than L86-M33 and cheaper than blox m10q. Doesn't have internal antenna though
NEO-F10N is too expensive, but it does L1/L5 and connects to all the constellations. Anyways this is a easily solvable problem for a later time.