opinions on TrainSignal cbts?

just looking for opinions on any of TrainSignal's cbts... good? bad? soso?

I just finished their DNS one and thought it was pretty good. Certianly
not 
enough to use as sole material for passing test (not intended for that 
anyway) but I was impressed. I am thinking about getting their package
deal 
with *all* the windows cbt's and want to see what other people's
experiences 
have been with them...

to be clear as possible here, I know and am not looking for these to be a 
one stop shop to pass a test. Several sources of study are required and of

course experience... what I am hoping to get are opinions from people who 
have used any TrainSignal cbts on their:

1) *accuracy of information*

2) level of detail covered for subject matter

3) instructors effectiveness (clarity in communication, explaining 
complicated things in easier to understand terms, good instruction etc..)