I've now replaced all 8 ceiling lights with the 5''White Shell with Switch, Warm White Lighting version. Still very pleased! Amps down, brightness up (at least twice as bright as the 10W halogen bulbs).
These are flush mount and require no holes other than the existing one that passes the cable through and 3 to 6 hidden screws (I've used 3 as they weight almost nothing). The white bezel clips on to cover the screws.