they have come down in price considerably over the last few years... especially internal models... especially the gkm and ebay models.
as far as STRONGLY advocating goes... i have one... plumbed in... and use it everyday... and can say without a shadow of a doubt they don't provide all the benefits people who STRONGLY advocate them BRAG about. (we know how peeing contests can get). the single best purchase one can put onto/into a tank is an educated one (ie: stocking with compatible fish or using the appropriate size filter (not according to manufacturers suggestions), co2 on a high light tank, etc., etc. ... i can think of a dozen better purchases off the top of my head [not that uv isn't great, mind you]).
as far as STRONGLY advocating goes... i have one... plumbed in... and use it everyday... and can say without a shadow of a doubt they don't provide all the benefits people who STRONGLY advocate them BRAG about. (we know how peeing contests can get). the single best purchase one can put onto/into a tank is an educated one (ie: stocking with compatible fish or using the appropriate size filter (not according to manufacturers suggestions), co2 on a high light tank, etc., etc. ... i can think of a dozen better purchases off the top of my head [not that uv isn't great, mind you]).
