Most of the people I see buying Furman's for home studios, don't understand the reasons of the problems they have and buy a Furman because they think it will solve the "noise".
But whats the Noise? Whats causing it?
Sometimes it's ground loops, other times bad cabling or wrongly connected equipment.
None of those issues is solved by a power conditioner, but people with less knowledge will resort to buying one thinking the source of "Noise" or "Interference" is the power lines.
Like Jakob said for surge protection UPS are quite good, cheap and available everywhere.
I'm not saying a Furman unit is not useful, to be honest I never needed one and I'm not familiar with all their products,
what I can say is that the most "Clean" studios where I worked didn't use Furman units, they just had very well done power connections and grouding.
The only time I used Furman units was in a improvised wharehouse studio belonging to an independent label where I normally do 1 or 2 records a year.
This studio is full of noise issues, it's actually the worst place in terms of noise where I recorded.
The owners got Furman units after the first records where made there in an attempt to remove the noise issues,
it didn't work, the Furmans didnt solve anything and everything is the same.
Theres low end hum in amplifiers, there's 10Khz tone everywhere, there's crackling noises that come and goe.
It's strange, also some days are better than others, pluging to the wall socket or from the Furman it's exactly the same.
There was one time with Keyboards that pluging to the wall was less noisy than from the Furman.
What I want to say with this is that it's not the power conditioners fault, probably the problem comes from EMI from the Railroad high tension lines on the other side of the wharehouse walls, so the Furman can't do anything about it.
With Railroad the Furman can't help
Without Railroad the sound would be clean and the Furman would not be considered
In the End I would get an UPS
If someone has a different experience please share, I would like to know in what situations the Furman power conditioners could be useful, so I can advise studio owners when they should buy one of those units or when not to buy
thanks