Sorry to burst your bubble, but you really haven't seen one yet. This has absolutely nothing in common with an insomnia sale. It's like calling HOMM3 a first-person shooter --- it doesn't make it one.

Anyhow, to answer your question. I haven't bought anything. The few things that I might have considered interesting, I either already own, or the discount was way too low. Still, there is one game on my wishlist that surprisingly isn't discounted, so it might still show up --- if it does with at a least a 50% discount, I might buy it.

Having the servers play up a few times early in the sale meant I missed out on a couple of the promos.

As someone else mentioned, they should run through them again. Maybe do a two hour each thing at the end of the sale.

There were several games I would have been interested in buying, but I already bought them either here or on another store.

I actually wish they had these sales branded differently or at least had the number of units sold and stock available hidden. Sales might have actually been better if it was hidden, and having it all on display for everyone to see just makes it even more apprarent how poor sales actually are on GOG. It certainly didn't paint a picture of an even somewhat healthy store front that's for sure.

In fact, it's looking like I won't buy anything at all on this years GOG Summer sale. I did have some wallet funds available thinking I would get something, but I'll just be holding it for one of the "Coming Soon" games I'm looking forward to now.

So far nothing for me.

The games I was interested I already had them.

I believe this Insomnia will last until the end of the sale, so there's still a chance that something that I want might pop up.

So far I bought nothing.

I hope you enjoy it. I came across it when I heard that the developer will stop making games. I have one of his games on my wishlist, but it'll have to wait for a bigger discount.
That's my impression as well. Like the aforementioned Narita Boy is an extra -10% versus the lowest discount recorded by IsThereAnyDeal. Blasphemous Digital Deluxe was just an extra -5% versus the public discount available now.
Yeah, since I owned the very first game in the sale, I thought they couldn't be bought as a gift at all. But you can, if you don't own the game. Seems arbitrary.
And I'm the happy recipient of two of those gifts. Thank you again.

The sale was still decent overall, even if the discounts weren't as great as in the past.
Btw I liked that the promo wasn't as hectic as the old ones.

Flash deals:
- Blood: Fresh Supply (just a cheap ok "upgrade" of the original I owned)
- Emperor: Rise of the Middle Kingdom (the Nth similar IG title, but should be ok)
- Blasphemous DDE (the best deal in the sale for me!)

Freebies:
- Beautiful Desolation (even if it has mixed reviews)
- Daggerfall Unity GOG Cut (sadly Gog messed up this pack)
(I already owned the rest, and I skipped the mediocre Venetica)

Normal sale:
- Alwa's Legacy
- Roller Coaster Tycoon® 2
- Quern - Undying Thoughts

Still in cart:
- Alien: Isolation Collection (I'd prefer to pay less..)
- Elderborn Metal AF (mixed reviews and slightly cheaper elsewhere)
- Ara Fell EE (maybe good enough?)
- Siege of Avalon: Anthology (flawed but nice oldie?)
- Cossacks Anthology (flawed but nice oldie? And better than the 2nd?)

I've bought 3 games so far. Only one was on my wishlist, and that's Blood. The other two, I must confess, were "impulse purchases".
I bought Van Helsing because of the high discount, even though I'm not a superfan of the genre and I certainly won't be playing it in the very near future; and UnMetal, since I like the vintage style and the humour (I very much enjoy parody or "spoof"), even though the discount certainly wasn't stellar. Indeed, I didn't feel totally comfortable paying more than 7 € for it, but in the end... I did it.
I already owned Machinarium, Disciples 2 and the Hitman games; and I didn't really care for the other titles on offer. I briefly considered Blasphemous but I'm not interested in the deluxe version.

My experience so far with the sale, then, has been very much "so-so". Let me briefly echo other GOGers above by saying that this isn't a real "Insomnia" sale, and to me it rather comes across as a not entirely successful attempt on the part of GOG to renew a link to the past, although, in all honesty, I wasn't that keen on the original formula (I actually missed some deals because I was asleep, then).
I, too, would have preferred to have more than one game on offer at a time (different genres, old/new, famous/obscure), with shorter time windows (and a second round in a different time of the day, for those who missed the first), and possibly higher discounts, although I realise this is not always feasible for newer titles.

Van Helsing offers you the option of not respawning enemies when you save and exit, allowing the game to be played more like Diablo 1 than the usual ARPGs. The game is also balanced in that you will hit the level cap a bit before the end of the game if you just go through and explore the game as you would a regular RPG, so no grinding is necessary.

Definitely a good entry level game if you are not a fan of the genre.

You're welcome.

I loved Diablo, so I'm glad to hear the game can be played in a similar way. I especially like the "no grinding" aspect. And I enjoy the gothic setting very much. Thank you.

I've only seen two games available that I didn't already own, and neither one spoke to me. So no Insomnia-specific purchases from me, at least not yet

Had already bought everything I really wanted. Nice price for Van Helsing, though. Record low.

I purchased Van Helsing and Blasphemous, also was so tempted for many others like Lego Batman, Shovel Knight, Star Trek Away Team and Death Trash, but specially for Mount & Blade 2 Bannerlord, I love that game series so much... But that price is scary, more with our country taxes of 74%, one day I will buy it, hopefully another Insomia Promo will appear :D

Any of the games I'd want to buy, I already did. Sooooo.... Not too well. If there was one I wanted to buy and don't have, I missed it. I can't keep logging in all day everyday just to see some pretty meh discounts on games I have nearly no interest in.