Intriguing hints regarding the technology involved can be found in the ship description:
The fact is, this “outlying cylindrical structure” looks a bit like a stargate, and is not dissimilar to components of the Villard Wheel mentioned previously. The mystery takes a further turn for diabolical if you consider EVE blogger Rhavas’ theory suggesting that the “shiny new cruiser is the Sisters’ tool to take the sacrifice to the altar for slaughter!”
The ships themselves will both be capable of fitting a Covert Ops Cloaking Device II, enabling them to warp cloaked. They also receive bonuses to scanner probes, making them capable of hunting down hidden anomalies and wormholes. In addition, they have an assortment of bonuses to their combat abilities, including increased drone performance and enhanced armor resistances.
Having briefly experimented with both on CCP’s Singularity test server, the Stratios in particular is an absolute beast, capable of terrifyingly high damage (800dps+) if fitted specifically for that purpose. To give that context, that is a damage range some battleships - two class sizes above cruiser - struggle to deliver.
Of course, to achieve such singular purpose so well must be at the sacrifice of other benefits, requiring multiple module loadouts.
This is a problem resolved by the next Rubicon feature, the mobile depot.