CUPS seems to be very unpredictable. I couldn't get older versions to work, at all. Then, it started working at some version, but I saw what Klipp is describing (perhaps even worse, because the system needed to be rebooted to get back into the CUPS control, most of the time). The very latest eCUPS seems to work a LOT better, but I found that I need to mix, and match, the parts, to get it to work properly, and I think there is still a problem with USB.EXE (I think I have the latest version, which is supposed to fix the problems), but I haven't confirmed that, yet.
Overall, I get the best results when using a WiFi connected HP D110a printer. I have a very similar HP C4180 printer, that is USB connected. I also have a canon i960, which works, but isn't perfect (it works better with the OMNI i950 driver).
At the moment, I get pretty good performance from:
cups-base-1_4_8_3.wpi
cups-1.6.2-backends-os2.zip (except USB.EXE)
cupsgui.wpi
ecupshp-pdr-20100304.wpi
ghostscript-8_7_1.wpi
gutenprint-5_2_9.wpi
hpaio-3.13.3-os2-20130526.zip
hplip-3_12_10a.wpi
USB.EXE, dated May 26, 2013.
You may need other packages, depending on what printer you have.
Oh yeah, the scanners both work, using the command line, but TAME can't seem to figure out having two scanners to work with.