Loved how this figure looks in T-Rex mode, after I bought it I fell in love with the robot mode. Highly recommend!

This is by far the most impressive and enjoyable transformers figure I've ever had. It is a tricky transformation (I suggest looking up a video). But it's gets easier as you do it more. And it's worth it. Both modes are clean looking and amazingly posable.
I love this figure.

Dino mode is AMAZING
Robot mode is AMAZING
Transformation is tricky but gets easier once you do it a few times.

This is a big, beautiful toy. I love collecting Grimlock and third party inspired toys of my favorite robot T-Rex. I think this T-Rex mode is the best of all of the interpretations. It is very IDW inspired and absolutely captures it perfectly. Both modes are amazing and have great articulation. There is also a little feature with light up eyes that is a cute bonus.
There is one little fiddly bit in the transformation so I recommend watching the video review from TFSource.
I give Cacus an overall 4.75 stars, the only real downside being the difficult part of the transformation, but I 100% recommend this toy. If you are filling out your Dynobot or Scavenger shelf, Cacus will be a highlight.