Although 18 bit 5500s are less dear, I'm unaware of whether they can carry the latest firmware. That made quite a difference to the clarity of the bass, etc., iirc?

Seems like the concensus is that 5Ks are more room tolerant (in my a experience they're among THE most tolerant, 'fit and forget' speakers around) but if you have the right space with either just the right dimensions/construction, or a good amount of bass traps, etc, 5500s might be just the thing?

HC: 861v4/ID40/LPS, DSP5000, DSP5000VC, DSP3100, SW1600, HD621, Oppo BDP-105, Sony VPL-HW55ES
2-Channel: Oppo BDP-105, TEAC VRDS-7/Trichord Clock 3/PSU, 551, Quad 303, Harbeth Compact 7ES-3, Kimber cables, Russ Andrews mains and supports.
Previous Meridian: 5000C, 5200SL, 7200.2, 6000, 562V.2, 568.2mm, 800v4, 808.2i, 818v2/v3, 861v8, 502