Haven't heard of either of these. There are a couple ticket scams going at all times, so if the deal seems TOO good to be true, it probably is.
There are some unscrupulous vendors who sell "used" tickets with a day or two remaining. These can be difficult to use, and if they sell you a 5-day with 2 days remaining, well you'll be out of luck! A lot of other discount tickets will require a timeshare presentation; legitimate tickets, but you have to decide if the price is worth the loss of a half-day of your reservation. Not saying that either of these two sites are involved in that!
The most popular discount sites are Under Cover Tourist (but get the code from Mousesavers.com first to save even more - you need to sign up for their newsletter, once a month list of all kinds of deals) and Maple Leaf Tickets. There are a few other that you will find recommendations for throughout the site. I would only deal with one that you find SEVERAL recommendations for on the Disboards. Best thread is probably the Budget Board here for tips.