My sentiments exactly. I also have the Slim Book (admittedly, not the best choice in name considering its heft) but it hit all of my needs. When docked, it resembles a MBP--my wife reached for the trackpad before realizing it was my iPP.

Yes, the keyboard portion is heavy but that heft affords a rock solid typing experience---infinitely adjustable viewing angles, full set of function keys, adjustable backlighting (color and brightness), pairing with multiple BT devices (I have mine set up for my phone and Apple TV as well) and ridiculous battery life. I'd have loved it to use the smart connector as well but it connects via BT before the iPP is fully open and has no noticeable lag.
And like Max mentioned, the iPP pops out in an instant. I also love flipping it around so that the keyboard serves as a stand, again offering whatever viewing angle you prefer.
If portability is of utmost priority, I think you won't find better than the ASK but you'll also be losing so much functionality.