SteelSeries lets you try the mouse for size and fit before purchase. That said, the shape of the Sensei [RAW] mouse is absolutely top notch. You will be hard-pressed to find anything more comfortable for long gaming sessions if you have normal-sized hands and prefer a palm-type grip.
The bundle is not particularly impressive, but it is a [RAW] product, so you cannot fault them for keeping it simple.
The structural layout of the mouse has been carried over from the original, which is a good thing. The cable entry is properly constructed and the cable has a soft jacket, which is nice.
SteelSeries has kept the original Sensei design apart from the fancy colors and the LCD display on the bottom. The sample we got for review, the brand-new Frost Blue Edition, is quite IceMat-like. The white and grey definitely suits the design and the mouse looks great, possibly even better than the shiny reflective design of the original.
The [RAW] edition might be a slimmed-down version of the original Sensei, but it still has a lot of great gaming features, like The DPI-adjustment button that remained the same, which is good if you are into using different sensitivity settings in-game.
The lighting system, which in my mind is completely superfluous on a dedicated gaming mouse, has been dialed back a notch for the Sensei [RAW]. The Frost Blue Edition has one blue LED illuminating the SteelSeries logo. Part of the wheel also lights up blue. SteelSeries gives you control over its behavior, and you can turn it off completely if you do not like it.
SteelSeries mouse feet have always been some of the best and still are. The feet are big and quite thick, so they will most likely outlive the mouse.
The scroll wheel is not super. It feels a little loose compared to other hardcore gaming mice and the tactile feedback is a little indecisive. It can still be used for weapon changes, etc., but you have to get used to its feel. The amount of feedback is ideal for desktop work, but some hardcore FPS gamers will find it a bit on the low side.
SteelSeries is using the Avago ADNS-9500 for the Sensei. It provides near-perfect tracking at all sensitivity settings. Its maximum tracking resolution is 5700 DPI, which is enough for most.
Side buttons are always hard to get right, but SteelSeries nails it with the Sensei [RAW]. Their actuation force is adequate, avoiding accidental key presses while giving you good feedback.