I signed up for the Target Test Prep service for a quick brush-up prior to my GMAT exam. I had previously taken the exam and scored well in verbal, but needed a serious quant boost!
After reading multiple reviews, I went with Target. I had my exam coming up in about a month, and needed some intensive core skills review + practice problems. The 'chapters' available on Target were an awesome way to walk through fundamentals. There was even an option for 'accelerated practice' which lets you focus on slightly more complex material.
The practice tests were comprehensive, testing a whole slew of possible GMAT areas. The answer explanations were thorough. There were also video explanations which I found super helpful.
The team was super responsive to any questions I had - both material-wise and customer service-wise.
Overall, I'd highly recommend.. especially if you need to focus in on quant over a short period of time! My score was much more balanced after studying with Target. Thanks Scott and team!