I purchased the white pastel version that looks great with my front iCarbon skin. The pastel version is a glossy plastic that does not feel overly slippery or uncomfortable to hold. As with my past experiences with the UTA cases, the fit is very tight with no creaking. I have decided to keep my back skin on to keep the white on white look thru the UTA's back cutout. Even with the back skin on, the UTA fits just fine.
As with most of the thin, snap-on type cases on the market, the UTA offers no real protection on the top and bottom of the case. But to be totally honest, it would take a severe drop directly on either the top or bottom to damage your outer band. The UTA does have a small lip that extends over the phone on the bottom, top, and sides to prevent contact from being made. The lip on the sides of the phone give the case a lay-on-the-table design so you don't have to worry about putting the phone screen side down on a table.
Overall, the SGP Ultra Thin Air offers mimimal protection in a great form factor. That's exactly what I want in a case and as such, is the reason why I continue to purchase them for my iPhone 4s.
The Ultra Thin Air is $21.99. You can find it and other great cases at the SPIGEN SGP store.