Aye, for the same reasons I gave up on gravel around the same time. When I only had one or two tanks, it was not an issue. However, with the current "zoo" I seem to be running in my basement zero substrate for aquatics is the way to go.
As I write this, I neglected to mention one other use for UG filters I swear by: drain access for terrestrial reptile and amphibian enclosures. This is truly the fastest way to ensure one has access to siphon out excess water in the event of over watering on a leaky water feature in an established enclosure. The risers are easily hidden, and a bit of synthetic cotton wool or a plug cut from open cell foam keeps the pets and live foods out, yet still allows air to circulate and siphon access.
I haven't used this in years which is why I had forgotten. However, I think I may spend the afternoon setting up a few US ten gallon formats with this method as both female Jackson's appear to be ready to drop young any day now. This rig was an excellent way to keep the tiny little buggers in the past in well controlled housing.