This price range doesn’t afford you too many options. You’re really at the very bottom end of CO2 lasers and a much wider range of diode lasers.
For CO2 you’re really talking about a K40 of some type whether from ebay or OmTech. OmTech will likely have better support and QC. To me the major drawback of the K40 vs a diode laser is the working size. You can typically get much larger diode laser frames for much less than a K40. If size isn’t a major consideration then a CO2 laser is going to be much more flexible in terms of what can be done with it. The single biggest factors being the ability to cut material and faster cutting/engraving speeds. The CO2 laser will cut through material much more readily and can also cut things like clear/light acrylic that are not possible with a diode laser.
Having said that, CO2 lasers are much more finicky and require much more support with things like cooling, more elaborate ventilation, mirror alignment, more components to maintain, etc. Diode lasers are tidier, more compact, lighter, and simpler in construction.
My general take, if the needs and planned uses are fairly modest then a diode laser is cheaper and easier to maintain. Once you start pushing the boundary of what a diode laser is capable of, it’s better to switch to a CO2 laser than force a diode laser to work to the edge of its ability.
Take a read here for my thoughts on Ortur if you’re interested:
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