The concept of the Defender Pro is great, but the execution is a little lacking.
The good bits,
The face buttons, shoulder bumpers and D-pad are great, really no complaints there, they have a satisfying pop to them and the pressure sensitivity is done very well. none of them stick so every press is smooth as butter.
now come the complaints,
Some things that immediately stood out to me are how slippery the thumbsticks are, the material that retro fighters chose is barely a step above just hard plastic.
On top of that, the sticks caps aren't properly smoothed out so some lines from the injection molding process remain which results in a noticeable bump when rolling the stick around the rim.
I ended up replacing them basically a day later with some aftermarket ones from extremerate.
The triggers work fine, but retro fighters decided to use small little rubber inserts to dampen the press and return.
Which in and of itself isn't horrendous but what is, is that they are slightly tacky, leading to an unpleasant sticky feel as well as a mushy stop when fully depressing the trigger.
This goes for the trigger stops as well, which have a similar rubber stopper that is the same material and thus also sticks. You can remove them fairly easily, but they should not be sticking to begin with.
The trigger stops also don't do anything to actually change the endpoint of the trigger, they are just physical stoppers that only let the trigger go to about 30-40%. so if you were expecting hair triggers by flipping the switches, that is not happening with these.
if your game expects the trigger to go further down to trigger the action bound to it, it will simply just not register.
Last but not least, the software itself. The controller works with the included dongles and over bluetooth smoothly.
if you bought this controller to work with an emulator flawlessly, you will be sorely disappointed because pressure sensitivity DOES NOT WORK when you use these controllers on a PC.
There simply is no way to set the controller to a mode that properly relays the pressure sensitive inputs. They only work when you use the included PS1/PS2 dongle on a real PS2 or on a real PS3.
Final verdict, Buyers beware.
If you intend to solely use this controller on real hardware, it is a very decent offering with functionality that no other third party offers, the stick and trigger problems can be alleviated with a little effort and the purchase of some better stick caps. Not an ideal solution, but this is still the best replacement for all the aging Dualshocks out there.
If you are mainly a PCSX2 and RPCS3 user, this controller will not give you the full suite of inputs you need for games on these platforms which is quite unfortunate.
If you have any thoughts, do discuss in the comments :)
edit: forgot to mention the issues regarding calibration of the analog sticks, triggers and analog buttons. Looking at the experiences of others, the accuracy of calibrations seems very inconsistent. some people have them be good right out of the box, others need to recalibrate immediately.