I ran lsusb for each USB-> serial adapter, and they are the same.
Bus 001 Device 005: ID 067b:2303 Prolific Technology, Inc. PL2303 Serial Port /
Mobile Action MA-8910P
Bus 001 Device 005: ID 067b:2303 Prolific Technology, Inc. PL2303 Serial Port
Mobile Action MA-8910P
Bus 001 Device 005: ID 067b:2303 Prolific Technology, Inc. PL2303 Serial Port /
Mobile Action MA-8910P
Bus 001 Device 006: ID 067b:2303 Prolific Technology, Inc. PL2303 Serial Port /
Mobile Action MA-8910P