This has to do with where the keys are set. Most people can play just fine on with an offset G key. If you have larger fingers it may be better to get an inline G flute.
Acoustically both inline and offset flutes are the same. Even though the Offset G Key requires an extra rod it will not be any more expansive to get repaired.
Since most models come in both inline and Offset, I would suggest trying both types and find which one you like best.
Notice how all the keys are "Inline" with each other.
Here the G Key (just right of the G# key) and the key to the left of it are "Offset" or pushed out.