We just set up a big display with a working Fluval G6 at my work, and they basically look awesome.
Everything is fantastic about them except the price, and the way that the pre-filter cartridge needs to be a Fluval one. That's not too bad though, as it does work very, very well with no bypass and the dirt collects on the inside of it. Plus the filter tells you when it needs changing, alerting you to a decreased flow rate.
If your on a budget, then obviously it's not worth it.
But if you have a very high budget or just really appreciate shiny gadgets, they are very efficient filters with what seems to be fantastic build quality.
I'm undecided on if I want to get one though, I could get a Fluval G3 for £240 with my staff discount, or couple of Fluval 405s/ Rena XP4s/Tetratec EX1200s/Eheim 2224s or even a Fluval FX5/Eheim 2078/2080, all options would provide a much better value for money approach, with regards to filtration efficiency anyway.
Just totally depends how much you like shiny gadgets, and your wallet
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