Heathrow Harry,
I concur with PAXboy and I too call bull !
Looking at their how it works page, it basically describes a travel agency process (a) fill out form or call, (b) they'll call you and offer you a quote.
Most of the things they mention are not secret and are far from being "not available to the public" (as they claim)... multi-airline travel, companion flights, mileage deals, last minute deals, long leg - short leg etc. can all be done direct by the general public.
There are also some very questionable reviews of them out there, such as
this one from Fodors ....
On the morning we were due to fly (in the car on the way to the airport), I received a call from an AFG representative. They apologized that our tickets had been cancelled due to “over-booking”
There is also another claim being made
on the "RipoffReport" website here :
They use their web sites
www.wholesale-flights.com and
www.alphaflightguru.com to make customers call them and while customer on the phone with sales agent they make bogus/illegal reservation in online booking system in order to grab all seats on certain dates and make them unavailable for others and maximize the profit
Obviously you'll have to make your mind up in relation to the claims, I've never dealt with the companies, I'm just passing on what I've found via Google.
As PAXboy says, in highly competitive industries such as the airline industry, the days of "doing deals" are long gone....in todays age of social media etc it would be neigh on impossible to keep them secret.
To be perfectly honest, as far as I'm concerned there's only one tool out there. Its called ITA Matrix, now owned by Google but thankfully they are still offering the independent more powerful search interface that doesn't require you to submit yourself to any Google stupidities such as requiring a Google account or whatever.
Take the time to learn it (for much time you will need !) and you will be rewarded with good deals on flights.