MIR Pro works great with many "average" modern i7-based machines. During a recent test I had almost 50 Icons on MIR stage while mixing in 5.0 (i.e. surround without LFE) @ 44.1 kHz. ASIO- and MIR's own latency were set to 1024 samples. That left plenty of resources to run Nuendo on the same machine (i7 3930K @ 3.2 GHz with 32 GB RAM).
I can run over 130 Icons on the samy system when I work in stereo.
Kind regards,
/Dietz - Vienna Symphonic Library