I agree with Kclone, definite synergy in staying with the same brand for amp/preamp. One of the best systems I ever heard was Meridian cd/pre/amp with Sonus faber speakers. Find a brand you like and commit to it. Mix and match approach can work, but is a harder to realize maximum potential. Move up the same brand range when funds permit. Its far easier, synergistic approach.
Benefits of brand synergy
How important is brand synergy in matching components? This not only includes amps and preamps but also digital sources from a particular brand, say Arcam or Kell. Is this "synergy" important just for impedance purposes or is there an additional sonic benefit of having everything matching? Thanks.