Everything I know about Rega speakers is that they are very good indeed for the money but may seem a little bright if partnered with bright side of neutral kit. My friend's R5s with the Mira3 and Apollo sounded absolutely superb, but when trying the 5s on my Rotel and Kandy CDP, things got a bit harsh (in my room).
Perhaps look to partner the R5s with a Rega amp as a starting point.
Rotel RA-03, Quad 405, MF X-Ray v8, Spendor SA1 and a load of other tat...