While the truest arcade experience will always be with an arcade stick (or an arcade cabinet, if you can afford it)... the
Versus Fighting Pad offers a very nice approximation in a gamepad form-factor. The
Versus Fighting Pad features a 6-button layout where the action buttons would typically be. The standard four action buttons are almost exactly in their normal orientation; they are slightly rotated clockwise, so that the first two buttons on the top row of buttons are (Square) and (Triangle), and the first two buttons on the bottom row are (X) and (Circle). The right-most pair are an additional pair of buttons that feel like the other (action) buttons, but are (L1) on the top row and (R1) on the bottom row.
Layout aside, the first thing you'll notice about the Versus Fighting Pad is that the shape is unique. The left side is bigger than the right, allowing you to hold it more securely in place with your left hand, freeing your right hand to either hold the controller as a normal gamepad and hit the action buttons with your thumb or to position your hand, palm-down, over the controller and press the buttons like you would on an arcade stick. Personally, I found that I switched back and forth between the two scenarios, depending on what fighting game I was playing and what character I was playing... or playing against. The palm-down arcade-button-pressing method allows more frenetic gameplay, but you might need to rest the right side of the stick on your leg if you really start going at it.
While the Versus Fighting Pad can be put to good use when you are playing strategically as a character you're familiar with, it is also, quite frankly, a button-masher's dream. The (Select) and (Start) buttons are "hidden" - tucked around the front of the controller (around the corner from the top of the face... just toward the center from the (R2) shoulder button). This makes it easy enough to get to - when you want to get to them, but nearly impossible to accidentally hit when tapping action buttons maniacally to generate a flurry of attacks.
The Versus also features a rubberized comfort coating over the most of the body of the controller, itself. This coating increases both comfort and grip.
One unique aspect of the Versus Fighting Pad is that the Action buttons are made with arcade style micro-switches... and the left joystick is, as well. Where you would normally have an analog stick and a D-pad, the Versus features a single digital joystick (think, "old-skool"), with the same micro-switch-based snappy action as the action buttons.