Warning for Beautiful BiOrb105 & Goldfish

My collection of little old goldfish will be 11 years old this month. I am a very experienced keeper. I felt I should warn about the very beautiful, but very poor design of the BiOrb 105. Do not buy a BiOrb 105 if you want to keep goldfish for the following reasons:(Based on ONE 7cm goldfish in 105lit tank) -

1 Goldfish create a lot of waste and the filtration system is not adequate to deal with amount of waste.
2 The pre-packaged filter kits are very expensive and must be changed far more often than is recommended by manufacturer. I.e. every week or two!
3 The tank mouth has a relatively small opening for maintenance, and it is not easy to use syphon to clear mess in bottom of tank, which accumulates fast under the ceramic gravel.
4 The soft plastic BiOrb syphon is very poor quality (valves not working), and you will need a better syphon. (Despite rave reviews on Amazon!)
5 The goldfish can damage their mouths on the sharp ceramic gravel when they try to hoover up food. Feeding is awkward as the food is sucked into gravel too fast and fish cannot feed well.
6 Aeration/ oxygen levels are too low for 105Lit. Air stones get clogged relatively fast.

My old gold fish are happiest in standard tank with really good filtration and aeration.They like sand rather than pebbles to hoover food. Sharp pebbles/gravel can cut mouths.