Z97 is more future proof (Supports Broadwell where as Z87 has no BIOS updates to do so).
that's true, but i wonder how often, if at all, that OP will upgrade. hence z87 and a full build including a ssd
Inferior monitor (he said gaming so the faster response time from the 1ms will reduce if not eliminate ghosting).
can always spec that for an extra £9 ;p
Slower GFX card.
not by much, 5%ish maybe? £36 difference though