I've run them both on the inside and the outside. I prefer the outsides. No imaging problems with mine, and I prefer the wider soundstage. Who is right in that unless one of your wall comes in at a odd angle, reflections both ways should be equal.
Carl.
Mains: Khorn bass bins, Altec A7s (Altec 902s, Trachorns, JBL E140s), center: 91 Belle; side surrounds: KG 3.5s; rear surrounds: 77 Belles (Radian 850s, ALK ES, Forte drivers), SVS PB12, Peach, Classe SSP30,MkII, NosValves VRDs, Sonic Impact Super-T, Dynaco ST 70, QSC PLX 1202, Crown Powerline 4, Yamaha P2200, Yamaha PC2002M, Jolida JD100 modded, Denon 2900, NAD 4155, Thorens TD160 Super w/Grado Reference, 7.1 in all. Oh, and some Phase Linear Andromedas and other stuff.
Family Rm: RB25s, RC7 (Dean mod), JBLs, Yamaha RXV1300, SVS 20-39PCi.
Patio: JBL 4612s.