I bought tickets outside the CWS one year and they were no good. Luckily the clown was in the same spot so I made him give me even better seats for the same money and I made him walk to the gate with me to make sure they were good.
I have used ticket services a few times. Very satisfied with them. The only time I bought tickets outside a stadium was to watch the Saints play in 96 the day after Florida kicked the Tigers ass in Gainsville. We paid 8.00 for two tickets. Even though the Saints beat the Bears it was a horrible pathetic game. It was like watching two bottom dweller high school teams play. The dome was only half full if even that. We moved seats every quarter and sat in both end zones and both sidelines. If I remember right the Saints only won 3 or 4 that year.