• Though it's plasticky, it offers up a well-designed body that's thin and fits into pockets easily
• 4.52-inch Super AMOLED Plus display is absolutely beautiful, though may border on the "too large" side for some
• Ships with Android 2.3.5 (Gingerbread) and TouchWiz 4.0, a drastically improved version of Samsung's custom UI.
• Supports T-Mobile's HSPA+ 42 Mbps standard, so data speeds are nice and fast

• Despite what most would consider a fast 1.5 GHz Snapdragon processor, there's noticeable lag in comparison to Samsung's Exynos CPU (which is found in the AT&T and Sprint versions)

Summary

The Galaxy S II line is arguably the most popular Android line in the United States (at the time of this writing), and the list keeps growing with the introduction of T-Mobile's version of the iconic device.  It branches off from AT&T and Sprint's versions by offering a dual-core 1.5 GHz Snapdragon CPU in place of a 1.2 GHz Exynos chip, along with a 4.52-inch Super AMOLED Plus display, 8-megapixel camera with 1080p HD video recording capabilities, and Android 2.3.5 with TouchWiz 4.0.  It's a high-end phone with an excellent user interface, but due to lag experienced on it that wasn't present in the other two models (likely due to the processor shift), it comes in behind the HTC Amaze 4G.