RetailMeNot used to be all right but nowadays it's pretty useless in my experience. almost all the "deals" aren't actual coupons and are more like advertisements.

Now they are all really scammy. I haven't found a good code in years. All those sites do is forward you to the site with a referral link, if you buy something, coupon code or not, they get paid for the referral (and possibly future purchases you make).

Best I can suggest is to attack their business model. Open those sites in a private tab, copy/paste the codes to your normal browser.

I dont have a lot of trust in coupon services since the honey extension was exposed for being malicious.