Overall I have had a very positive experience using the Steam Controller. However, this is not saying that it does not has it's issues. Just going to lay it all out!

Pros:
-The controller simply feels great in my hands. Easily the most comfortable controller I have ever used. I feel like most controllers are just way too small for my hands.

-Ridiculous amount of customization. This by far is the greatest part about the controller. You can change and adjust everything on it. I can play games without moving my fingers off buttons at all. It is simply amazing. If you are playing a game and something feels a little too tight or loose, you can adjust it on a slider somewhere. Definitely takes some time to figure everything out, but the sky is the limit when compared to other controller hardware.

-The trackpads are great. However, it is going to take some time to get used to using the Steam Controller. It took me months, I am over a year in and I still feel it is a little odd sometimes. Once you get the customization tools down and the use of the trackpads, you can do A LOT without having to move your fingers to other buttons. I also find the accuracy in FPS games (when dialed in and trained) is superb to that of an analog stick. The Mouse to Joystick is just amazing. However, I had had some issues playing twinstick shooters, as the trackpad is very large compared to an analog stick ... I often lose track of where my finger is, which makes gameplay frustrating at times.


Cons:
-Non-Stop Beta, every day. There are constantly updates to the Steam software, and you really should be using the beta client if you want the most compatibility out of your hardware. I find the constant updates tiring and have seen them break a few things as well.This is infuriating at times when something has worked the day before, and is completely broken the next. I would have hoped the software would be more nailed down by now.

-Compatibility issues are another issue I have had on a number of products. Many of these problems stem from other input devices I have connected to my HTPC, but I have also had games work, and then never work again (Kalimba for example). It is frustrating when you have issues with the controller, and is definitely MUCH different in that respect to console gaming.

-No D-Pad. This is probably my number one issue with the design. I use a controller for side scrollers, platformers, and games that should be played with a controller. If you are playing an FPS game with a controller ... just stop. The clunkiness of the left track pad doesn't work well for a proper D-Pad in the slightest. Would love to see a modification or improvement to this.

-Rechargeable batteries are hard to get out. They must just be slightly larger than normal AA batteries. I am not sure. But both my Duracell and Energizer rechargeables are hard to get out and end up getting damaged occasionally when trying to eject them. I hope this is improved on a new version.

-I love the back grips, but my door slides back and forth and can feel like a button press, when it is not. This happens on 2 or 3 of the 4 controllers I have. Would love to see this tightened up for a new release.

That is about all I have. At the end of the day, I am very happy with my purchase of 4 controllers. Playing on the couch again with friends is just awesome. While the learning curve is uninviting, most people seem to pick up the button layouts quickly and can get into enjoying the game fast.

I hope this review helps and would definitely recommend the controller over most others I have used. Though, if a new version is released, I hope some of these improvements could be implemented. It would be amazing if you could swap the track pad out for a D-pad somehow, and still have it be robust. Happy gaming!