[nwh]

What's the driver support for dot matrix printers like in linux these days?

[brudgers]

Given the business use case, I doubt it is worse than for consumer oriented models.

e.g. http://www.okidata.com/drivers

Also, keeping in mind that dot matrix printers are old hardware, there has been a long time for someone to write a driver:

e.g. http://www.openprinting.org/printer/Oki/Oki-ML-520