The nivos are great as a sorta ride quality/height/mechanical complexity compromise when they work at new spec, for what they are, for their time?
That said, most were made by Sachs/Boge and the re-pop Sachs/bBge shocks I've gotten of late have been defective junk that doesn't last.
Maybe the Nivo-craps are different since they still use them (or the parts inside them???...hopefully) on new cars that have to last the stringent OE warranty and OEM manufacturer high volume quality control standards?
I did the conversion on a few cars...I find it perfectly acceptable as a compromise;
-lower cost generic shocks
-Variety of brands of replacement shocks that are replaceable or rebuildable with good longevity like the Bilstein HDs/DeCarbon mono-tubes.
-Only replace 1 wear part that just does the damping function, not the airbag & air pump function.
-Doesn't sag while parked with weak weenie springs that are prone to becoming smashed beyond repair.
That said, I don't wanna crap on the Nivos too much as I like them when they're new:
-Load leveling is nice
-No electric pumps or hoses required
-Not as complicated as a Citroen, Benz, Infinity Q45 'active' suspension hydra-pneumatic setup, but ride uh...almost as good as the rubber-dampened nitrogen bomb/no springs at all, but does have supplemental simple mechanical coil springs on a suspension overbuilt with strong mounting points for both the 'shock' (w/built in air-bag & pump, essentially) and 'spring.'
-Only 2 of them to deal with on the rear wheels of the volvo.
They do ride pretty dang nice and let you pick up a load of lumber, some pavers or few sacks of concrete or whatever or drive a few fat people in the back seat of your grandpa series or V70XC/V70R and have it handle pretty ok without having your headlights aimed at the sky either?
$200/shock for the V70XC or speshl part # nivo-crap for the V70R tho
...just been hoarding very lightly used ones rather than do the junkyard conversion from the S70 AWD junkpile.
At that price the quality control/longevity better be good! owww
I used to get ~10/yr/100K federally mandated chassis lemon law obligations or manufacturer extended warranty periods on avg roads/driving habits/use out of them?
Not too terrible?
Conversion isn't as easy or cheap for MK1 7/9 IRS guys...junk the car/it's not worth anything anyway/shocks are worth more than the car and apart from the 780...uh...hideous dated electrically laden 'yesterdays obscure limited production volume obsolete luxury car', or in the case of the 780, has rare parts is prone to rust and totally useless and *kinda* dated looking but less hideous than most 7/9 cars.