I have to agree that at least 90 days is required to evaluate a product for purchase.
Personally any product that asked for a credit card for a trial evaluation I would immediately pass on.
I can't remember a 30 day security software trial {especially the big companies} that ever asked for a credit card.
"we won't make you give a credit card" is therefore no incentive for a trial evaluation especially one for 30 days.
Don't take offense this is just my personal opinion,as the only time I am giving out my credit card is for a purchase.Appreciate the offer,as it is a very good product,but as others have stated 30 days is just not enough time.