Ice Cap in sump UVs

[Char.toombes]

Who has any real tangible experience with these newer Ice cap in sump UVs, specifically the 18W & 27W models? I am building a UNS R90 setup and would like to add a UV but after ordering and realizing how big a 27W high output UV is and its plumbing needs, these look way more attractive. I’d assuming I’d have to run the main pump in the skimmer section w/ return into the return chamber.

Any input is appreciated