I have both S2 and SP10 in my racks...
SP10 is second to none in build quality and reliability.
S2 was built to be a cheap box they can just toss at customers and lower the price as needed -- like the S1.
My S2 arrived as a pile of parts, i had to reassmble it and 4 of the hash boards were damaged in shipping so its hash as about 600 GH/s. Trying to get replacements but communication is difficult.
SP10's are super high quality, very solid performers and a bit better power efficiency. The web interface is very straight forward and simple to configure.
@ $3200 SP10 group buy VS $2599 for the S2, i would (and did) pay the extra money and buy the SP10 all day long. Both should ship within a week or two.
Second that. Spondoolies is the mercedes of mining hardware. s2 is a cheap nissan sunny.
WTF these are bitcoin miners, as long as they do their job as specced who cares what they look or "feel" like?
I want to know my stuff will work when i get it and i'm willing to pay reasonable premium to ensure that. I'm still trying to get the S2 repaired so it is definitely not working as specced. I know that Spondoolies-Tech would overnight me a replacement box if i received a DOA or damaged box. They are a top notch company that will stand behind, and are proud of their product.
The S2 definitely has its place and they will sell A LOT of them, but not everyone has the same objectives.