I got a new Razer Sabertooth gamepad (xbox 360 compatible).
I thought I'd post some observations.
The only "good" important differences from an Xbox 360 controller are:
(1) some limited functionality in being able to assign any of the regular buttons (including dpad) to one of the 6 extra added buttons (2 two position rockers on the bottom (for 4 buttons total) and 2 added buttons near the Bumper & Triggers.
Note: the original button still perform their function also.
So other than allowing you to have the old buttons in the new positions which may be useful there is no other advantage. They are NOT 6 new Input buttons - just assignable to existing gamepad buttons.
(2) You can use the Program mode to increase or decrease the sensitiviy of either or both Analog sticks (but NOT the Triggers) between -10 and +10. It is useful and you will see why below.
The sticks seem to react better than the Xbox 360 in terms os sensitivity, aka, they are more sensitive. EM Medium Sensitivity on the Razer is more like High Sensitivity on the Xbox 360 which is good in my opinion since on the 360 I had to use Medium and Deadzone 2 to avoid drift and allow fine movements in Pitch, Yaw, and Roll and lost some Combat response.
The Razer, so far, I'm using Medium and Deadzone 1 and get the Fine movement but still Combat reaction and max stick movements (using Left stick for Pitch & Yaw) and Triggers for Roll and Right stick for Strafe (but I have Razer Right Stick internal sensitivity set to -2 rather than the default 0 (to avoid the Back Y/return center Drift problem - see below).
Now for the Bad.
The Analog are the same cheap, lousy, sloppy sticks as in the Xbox 360 - meaning - they (and MOST ESPECIALLY the Right stick) do not return to Center values (32767).
The Right Stick, just as on the Xbox 360, may return + or - 100's or 1000's of 32767. On mine the Y axis is worst and moving it back and returning to Center may leave the Raw data value at ~ +37500. Oddly moving it forward does return to 32767. The X axis may return to 33000 to 34000.
The Left stick has the same problem in it's Y axis.
I find the Dpad better (for me) than the Xbox 360's Dpad which was pretty bad.
I think my conclusion is going to be that the Razer is NOT worth the $80 it cost because of the lousy Analog sticks.
If it was possible to assign diagonal (X) Dpad presses to the 6 new buttons I would be far happier, but you can only assign the 4 cross (+) dpad buttons to six.
It looks like no one is putting good quality analog sticks in Gamepads - and as I read somewhere else - they do exist because they are using in R/C planes & boats.