If you're looking for the most processor for your buck, the Surface's Quad-core NVIDIA Tegra 3 would play a large factor in your decision. But that's the difference between hybrids and laptops. Where bragging rights on laptops where earned on processor and RAM, on hybrids they're on display, battery life, and versatility.
None of these 5 hybrids separated themselves with a display better than 1366 x768. In contrast, the iPad's Retina display has a 2048 x 1536.
Long battery life like the 16 hours battery life in the Lenovo Ideatab is a game-changer -- beating even the iPad by 5 hours. For the first time, a laptop/hybrid user can do work without being tethered to the wall and not race the power indicator to zero.
Other than the HP Envy, the pricing is deceptive because to get the real value out of these hybrids, you'll need a keyboard, which can boost the price as much as $180. But in some cases, the keyboard increases the value because it extends battery life.