The farther you throw, the more the distance gap between your drivers and mids will widen. Also, if you are throwing nose up a bit with the drivers, then your distance gap will be even smaller because the drivers don't work well on nose up throws. With 250' on your mids, you probably will see better results throwing your fairways for any longer shots where placement is key, and leaving the drivers alone except for max distance drives.
Work with all your discs in a field and see where they all land. Focus on a distant target, and throw all your discs toward it and see where they land. I bet your fairway drivers will be closer to the target line and probably about the same distance as your distance drivers.