Fluval external 307 filter

Has anyone had the fluval Roma 240 and used the fluval external 307 filter Are they any good please I want to upgrade to a bigger tank Thank you I have, mine was a 306 filter - so I upgraded it to a 407 as mine is quite heavily stocked. But I’ve still kept the 306 As a backup just in case anything goes wrong. But I’ve not had any issues with it at all and really like the filter. What size tank was you using it in please