once you redeem a code, do you need to use asap? or does it last if you need to check out the product before deciding to use? can you see which codes are valid/active and time to expiration of discount?

Codes in the newsletter usually have a timer, also visible in the newsletter, ticking down until the time they can no longer be used. As of me posting this response, the Deadfire discount code has a little over 31 hours (also visible in the email: The offer ends on October 16th, 2019 at 1 PM UTC.).

Also in the email:

"Please be sure to complete your purchase before leaving the checkout page, otherwise your code will expire!"

Which just means to use it before the timer is up. I was curious about the price when I first read the email yesterday, saw it and decided I wasn't just shy of ~$30USD interested in the game but I just re-attempted to load the code and it's still working as if I'm going to purchase it... so, as long as the timer isn't at 00:00:00/1 PM UTC, you should be okay to purchase it.

As to it being 1 time use or not, for someone with the money currently and a bigger interest in the game than myself, here's my discount code:

-code's been used, thanks for mentioning it Mortius1!

If you use it to buy the game, leave a reply and if you're someone else who attempts to use it and finds that it doesn't work... also leave a reply.

I guess gog hired some behavioral psychologists to their marketing department. This ticks all the boxes. Through these mails, they are creating the impression of exclusivity (special secret discount just between the two us us) and time pressure (just one day and the offer will be gone).

Very shady practice from gog. I am very disappointed. If you want to put something on sale, do it the usual way. Skip this new marketing crap and throw that behavioral psychlogy manual to trash. We are your customers, not your monkeys.

It now gives an 'already used' error. Many of the last major sales have had time limited offers, ranging from 1 day to 5 hours.

Apart from the incentive to sign up to the newsletter, I can't see a significant difference. What is nice about their approach it is they are very clear about offer expiry, as opposed to a "while stocks last" sale.

I explained the difference in the first paragraph.

To further illustrate my point, I am giving you title of the email, that I received from gog:

"Psst... Don't tell anyone! Here's your HIDDEN DISCOUNT".

Lower in the mail is an active countdown btw.

As I said, to me, this is very shady marketing. Aimed at people who are easily manipulated or who dont have enough self-control. CDPR is strongly pro-consumer company, right? So no lootboxes, good DLCs for good prices etc... So let's make sure we held them accountable for this kind of behavior.

Thank you for mentioning that.

Oh. Clickbait.

I stand corrected.