Is questia.com Safe?

Signed up for a free trial. Didn't get the promised access password sent to my email address. Wrote to support - no answer. Further attempts to access the article I needed also failed. So I thought there was a bug during subscription process, my info was lost and the subscription failed overall. As I couldn't access the needed materials, I just let the site be and didn't return to it since. Still, several days later I started receiving email advertisements from them, which indicated that maybe the subscription went through, in the end. Still no password or notice from the support. So I checked my card balance and learned that some money went missing. Checked with my bank - yeah, charged from Questia. Tried to access the site again just to make sure - failed. Eventually, went to the bank and changed my account to stop Questia from charging it. WTF was that?

I created an account with this website, and wanted to pay for one month, but they took money from my card for half a year. Beside this, there are a lot o f books and article were can be found only summary. But I think once you pay you should get all the content of a book or an article. It's not a trustworthy website.

Had a problem when trying to switch from an automatically renewed subscription to a quarterly one. Fee for the quarter was taken, but access denied. Subsequent email requests for support got replies that didn't address the issue, or were ignored. Eventually sorted out the problem over the phone, but made me anxious about giving the company automatic authority to deduct money from my account.