In all seriousness Budrew, I was using ProAc Response 1SCs with a Blue Circle BC21 in the mix in relatively small room. I also have Audience AU24 speaker cable as part of the system.
The 1SCs are great little monitors [I also own Tablette 50 Signatures] that create a big yet focused image and they sound great with acoustic instruments and vocals.
The 1SCs have a character that can change greatly depending on what electronics are mated to it. They seem to really shine with tubes somewhere upstream, because valves seem to unlock the organic nature of the ProAc sound without compromising their detail.
One drawback to using newer ProAc monitors is the use of rear ports, so they need to be away from rear walls which could be difficult to achieve in a small room. But, ProAcs are very good for nearfield listening, and properly set up they can absolutely disappear and create a holographic soundfield in front of you.
I've heard the Spendor S3/5s, but that was at CES with Talk Electronics in front of them, so I can't make any direct comparisons. But I did compare the Sonus Faber Concertinos to the Tab 50 Sigs and thought they were very different. Both sounded organic, and while the Concertinos had a woodier, earthier sound and created a wider soundstage, I ended up keeping the ProAcs because of there sometimes scary and realisitc soundstaging ability.
I still own the Tab 50 Sigs and have been mostly using 1SCs for the past two years. Both are excellent. If I had to contrast them I'd say they were the same "person", but at different stages of their life. The 1SCs are that person at age 35, whereas the Tab 50 Sigs are that person during their college days. Does that make any sense?
I just got Response 2.5s last week and have been greatly enjoying them, even in my small room.