Which printer is better to print negatives on?

     
Choice of machine...

Inkjet
All inkjets can print negatives directly, but you have to optimise the print settings. Very basic HP Printer Copier Scanners (PSC) are the best.

Laser
Most will not work. All HP's can be darkened with laser toner density spray, the HP 1018/20/22 (running the 12a cartridge) although discontinued is the best for delivering a lot of toner cost-effectively.

Making them black (enhancing)...

Inkjet
Not required, output is usable straight from printer.

Laser
Nearly all laser printed negatives will require enhancing. Enhancing is done by wiping with turpentine (or a more agressive solvent) and heating. Alternatively you can spray with an aerosol of laser toner density blackener.

Cost (estimated)...

Inkjet
Printer = $100
A4 film = $0.40
Plus ink costs

Laser
Printer = $150
A4 film= $0.20
Plus toner and enhancing costs

Time...

Inkjet
Print = 10 secs

Laser
Print = 10 secs

Quality...

Inkjet
600 dpi min
Enhancing = 1 min

Laser
600 dpi min

Durability...

Inkjet
Last about 10 times, can be scratched or dissolved in water.

Laser
Very durable.