IMO the Leema, no doubt, depends on what your looking for, I agree with regards to the Naim but it is a bit quirky to live with and the Leema looks great, esp. in black, and has a phono stage.
Leema has a great sound and am sure you will get many owners here to confirm.
Unfortunately I am not able to demo the Leema but I will be able to demo the Cyrus. Would I be better spending the £600 on a Rotel 06-SE, Arcam A18, Brio R, Mira 3, NAD 356BEE ?
Can't comment on the Cyrus 6XP, only heard the latest 8XPD... the Leema whams all sub-£1,000 integrateds I've heard, including the Cyrus 8VS2. In saying that, if you partner it wrong, speaker-wise, it won't impress.
For the Leema I'd personally recommend MA (RSs, GS and GX ranges), Totem Arro, Spendor SA-1. These are the ones I've heard, otherwise consider Dynaudio, B&W or Epos.