I recently (this past May/June) purchased 5 Alen Breathsmart Air purifiers. I needed 2 in my bedroom due to high ceilings. I replaced one of the Breathsmarts with the new 75i. My sleep had greatly improved with the Breathsmarts but I’m really impressed with how much my sleep improved with the 75i. It’s a bummer these were not available when I made my original purchases!