I think you have to comparison shop.
I have bought coins from this company in the past, their deals on
ASE's and westward nickel sets have been the best I could find certain years. I Bought their
ASE's in their "showpack" packaging and just cut them out of the packaging for my Dansco album.
This offer sounds like a loss leader to me. If it is as described, the company is willing to pay a small premium to get you on their mailing list. After they send the coins advertised in the ad, they will then send you coins "On consignment" I think is the term they use. They'll send you some common modern coins which are way overpriced, but you just send them back in the postage paid envelope, no questions asked. You'll also get catalogs in the mail and if they have your email address, email offers. Occasionally they are worth buying, but you have to compare them to deals elsewhere
Usually you can find a better deal elsewhere, but for this deal it may be worth your time and effort.