Surge protectors and power conditioners - Good idea or bad?

Unless you live in an area which is frequented by lightning strikes or your power company executives are crooks, they are not needed.

Whole house Type II (at the panel, not the service entrance) and a large (10kVa) iso transformer with additional surge protection that feeds the sub panel for the system. Texas can get some big-assed storms, though Austin seems to be in a semi-protected pocket; still, the intensity of some of these storms is quite impressive (and somewhat scary) even when we are on the edge of them.
Back east, NY metro, north of the city along the Hudson, the infrastructure was really dated and we'd lose power even in a mild storm. 
The surge protectors won't do anything for brownouts (voltage drops) but I'm generally aware of the state of the grid here and when it gets to be 110F, I am less likely to play the system. Of course, my faith in the robustness of the grid here in Texas was put to the test during the recent ice storm that caused us to lose power for 4.5 days in bitter cold weather. 
The cost of whole house is well worth it; you don't need to buy the uber audiophile one, but can rely on units using MOVs. They'll degrade and you replace them. Obviously, with a direct strike, all bets are off. One started a fire and burned out a fairly large commercial/residental building in the adjacent town to us along the Hudson. I met a guy who got hit a decade before; he got up after the event and finished work. He later went home, where his wife discovered the bottoms of his feet were scorched. He progressively lost heart tissue and at the time I met him, was going through medical procedures in anticipation of a heart transplant. I think a healthy respect for those bolts from the sky is sensible. I used to unplug my main system during electrical storms back east. 

When I built my Bob Latino amp, the instructions explicitly said to not attach the amplifier to a power conditioner. I didn't quite understand the explanation, but leads me to believe that it is not an entirely neutral thing to add to your power. 

I live on a hill near a larger hill that often stops rainstorms.
The house is tall and has a lightning conductor running from the top of the roof down to an earth rod.
Lightning will always take the shortest/easiest route to ground so it goes that way and doesn't impact any of my electrical installations or cause any fire.

I live in an older, poorly grounded home in old suburb with an overloaded grid. I have most of my equipment hooked to power conditioners, except my amp. I based this decision on advice from electronic "experts" that certainly know more than I do. I don't hear any difference from when the equipment wasn't hooked to power conditioners.

That being said, my televisions do have less artifacts in low light scenes, now that they are hooked up to power conditioners. I also saw some general improvement in the overall picture quality.