As you're using a Sonos amp, you'll be wanting to utilise the power it has as much as possible. Try and stick to efficient speakers (nearer to 90dB), and ideally a nominal 8ohm load, but this isn't a necessity.
The SVS speakers you mention are worth a try, but also look at the Revel Concerta M16, KEF R300, Ophidian Mojo, and Golden Ear Aon3. If you read up on these, you'll find they cover a range of sizes, depending on your needs. The Ophidians can fit in the smallest of spaces, and are a surprisingly capable speaker despite their diminutive size.
How well these speakers will sound on the end of the Sonos really boils down to how good the Sonos actually is, and what your music source is. If you're using the likes of Spotify or iTunes, you'll be needing to look out for speakers that compliment compressed music, and help to liven it up somewhat - some compressed music can sound a bit on the dull, flat side.
Most of all, audition and see what you like the sound of.