Pros
NONE! They have a monopoly on the product which is just ok but the internal practices and lack of morals at this company make it really hard to say anything positive at all.
Cons
This company is like no other company I have ever seen. They took a young up and comer who actually liked working at the company and sent him to HQ telling him they were going to record him selling Loopnet so that they could teach new incoming training classes. It turns out that the CEO used this recording for his Sales Kickoff the following year to show the rest of the company that even good reps don't sell the product correctly. This rep sat their in front of a 1,000 people at sales kickoff watching the CEO show his video and pausing multiple times to basically humiliate him on his presentation. That rep was a Presidents Club winner and quit about 3 months later if not sooner. That sums up CoStar!