I had to buy some replacement pre-filters for the Inovaair E7 air purifier so I might as well give a mini review after living with it for about 9 months.
Fan is a ebm-papst R2E190-RA26-51 made in Germany, rated 57W but the unit seems to under drive it at 36W on high. This fan is like ~USD110 on Mouser so I seem to be getting my money's worth haha (purifier was ~USD510).
Chassis is 5052 aluminium, with a Dulux powder coat outdoor rated for 10 years, so will last ages indoors according to the manufacturer. It has held up just perfectly fine even if I use it as a makeshift nightstand.
Run capacitor is a Hydra MKP series, 400V AC @ 30,000 hours 85C.
Crimp terminals are TE Connectivity/AMP nylon, quite impressed they didn't just use some cheapo PVC rubbish. Interesting that they soldered the earth wire on the IEC inlet but used crimp terminals everywhere else.
Latch is branded Nielsen Sessions, it's very sturdy. The plastic carrying handles are branded Elesa Italy, made from PA+GF (polyamide with glass fiber)
The main HEPA filter is rated for up to 3-5 years (USD145), thanks in part to the prefilter which has to be replaced about every 6 months(USD18, not tooooo expensive). They say you should replace the prefilter when it gets 2mm of dust buildup which was 9 months in my little bedroom though I could have stretched it some more, it's kinda hard to eyeball.
The unit itself is made in Australia you bloody ripper. Everything looks easy to replace/repair so it will last a lifetime, none of that microprocessor controlled smart bluetooth consumer garbage with RFID-tagged filter replacements ahahah.
You know I actually had a little buyers remorse just after ordering because maybe I should have bought a cheapie $200 Xiaomi purifier or similar instead, but after using the air purifier and doing the teardown I think it was worth every one of the 700 dollarydoos.