Best printing protocol for hp Laserjet printer?

I have a small office network of 12 computers running 10.4.11 and 10.5.6 and 2 hp Laserjet printers. I have historically used Bonjour to set-up the printers, but have found that periodically the users cannot print because the printer cannot be found. This seems to happen randomly or if the ethernet is ever unplugged/plugged into the printer. I have to delete the printer and re-add it to return to normal functionality. Obviously a pain for multiple computers. I've recently explored the use of the IP printing to these same printers using "IPP', "LPD", and "HP Jetdirect Socket" and the printers IP address on the network. This set-up seems to be more resilient to changes, however, I do not know enough about the different protocols to make an educated decision on which is the best for this environment. I have found that I can print remotely when connected to the VPN through these protocols.
Can someone please advise which protocol would be best suited (and why)?

Thanks