@giZmo350Your results confused me initially, until I realised they were probably in kilobits per second. Note that kb is kilobits while kB is kilobytes.
FWIW, I usually speed test Amiga network cards by doing transfers to/from a local FTP server. These are some results I got for 3c589.device:
A1200 '060: 859kB/s upload, 752kB/s download
A1200 '030: 299kB/s upload, 384kB/s download