I just tried this and got "read_log.sh: line 14: ./gpsbabel: Permission denied." Any suggestions?
BT747 has a command line interface too, so I would suggest that somebody tries to get that running on Maemo to check out the speed of that. Regarding the download problems with BT747: did you try to adjust the chunk size, read ahead, .... These parameters influence performance on Maemo. Further, if there is a better connection method on Maemo, that can be taken into account.