Paul,
We are talking apples & oranges. The Surecheck TS is a passive alert and sells for $250. The Garmin 330 sells for $4500 and gives you much more accurate and useful traffic information. You could also look at the Ryan Systems for $8000-$30000 if you have the cash.
For $250, you get what you pay for. Minimal money = limited information. I will probably upgrade my Garmin 327 to the 330, in the near future and link it to my 530.
I would not recommend the Surecheck TS if you are looking for life-saving technology, however, for $250 it does offer some degree of added safety.
Gary
N116RC