for the most part they are brilliant, been using them for the past 5 years,
think mine was £240 when I got it. The only downside is if you're using it
in confined spaces or welding small structures where part of what you're
welding may cover the sensor above the visor this will cause it to go light,
also some of the cheaper ones I've tried work well for Mig and stick they
are not to good for tig welding where again they dont seem sensative enough
to DC welding to work correctly.