Another T4x backpack quiery - search didn't help

[alexzabr]

Sory rising up another backpack-related thread, but searching through numerous of such on the forums heer didn't help to resolve mine..
What I need is a simple backpack to carry my t43 with its power supply and also study stuff (you know, some books, writing accessories, some personal stuff..).
What is improtant is that I'd certainly prefer the one that has internal, detachable padded laptop carrying flat bag with its own straps, so that once getting to the location (a class or any other) I would be able to detach the laptop part and carry it out with me on the shoulder, this would free me from lugging the entire loaded backpack with me for a short being out of class, for instance (leaving the laptop without attention will lead to loosing one (can be stolen easily)).
So far I wasn't able to figure such backpack, all models just offer a built-in laptop compartemnt, but not the internal detachable flat/slip padded one, although many of regular shoulder laptop bags has such internal part.

Will be grateful for your assistance..