I know a couple of people with them who are happy with them due to price when compared to Eheim. They just buy higher quality media (Seachem and/or Ehiem) to fill them. My biggest concern is how long they will be around, and will there be spare parts in another 5 years? My Via Aqua heater turned green on the inside after less than 6 months. In my opinion if you plan on keeping fish for many years and can afford it, then go Eheim. They have been around for many years and you will probably be able to buy spare parts for them for eternity.