Could you try the following:
- Connect both laptops via wired network. Test the speed. If it is still slow then the problem is not in the wireless part.
- Connect one of the laptops via its wireless access point. Keep the other connected via wired networking. Test again.
If things are slow then test that laptop via the other wireless access point. This may show a problem with one specific combination of access point and wireless. - Revert the just tested laptop to wired. Connect the other laptop to its wireless point and test again.
If things are slow in step 1 then the problem is not in the wireless part. Maybe the connection between the two access points it bad. Maybe a laptop is slow in providing the data.
Steps 2 & 3 should allow you to eliminate a possible problem in the combination of one laptop and its access point.
If none of these shows anything, try transferring different data. (E.g. use a benchmark tool, or switch from CIFFs/Samba to FTP).