Mirror lenses - are they effective?

I am thinking of purchasing a telephoto 'mirror' lens - what is the general feeling towards them, and what is the quality of this type of lens.
Thanks

They will do if you can live with the fixed aperture and
'Doughnut' bokhe in background. The price is right though.
Best regards,
/Clay

There are many 500mm mirror lenses on the market and the cheap ones are dreadful. Reasonable ones are the marque lenses and also the Tamron and Tokina.

A couple of 350mm lenses are reputed to be good. The Russian 1000mm ones also have a reasonable reputation.

Be careful of mirror lenses as they are very susceptible to shock damage, so they need to have been looked after well.

Personally I don't like them much.

Hope that helps!

John