I don't have experience with the MaxUpgrades and Shinza products mentioned, but they look like they're worth checking out. FWIW, the sleeves I've used (below) use neoprene rather than the polyurethane of the aforementioned makers. I like the Waterfield Designs sleeve (www.sfbags.com). It closes with Velcro'd nylon webbing, and there's another loop of nylon webbing at the other end of the sleeve, which I find handy for fishing out the computer. Additional features are available, such as choice of horizontal or vertical orientation, full flap closures, straps, etc. Some people like the Tom Bihn designs (www.tombihn.com) which I've also tried, but I find the full sleeve flap (Velcro closure) doesn't really make a difference when it's riding inside another bag, except to add a wee bit of bulk. Romain