I got to say that I have mixed feelings about this PC. I gave it 3 Star because it is not bad and I had no issues with setting it up nor any of its components. BUT I was expecting better performance after the amount of money I spent ($1,220.00). I was hoping to replace my main PC with a small form factor "HIGH END" NUC PC.My NUC Specs:32GB DDR4 2133; 512GB 950PRO M.2 (Running OS – WIN 10, M.2 Running at 2349 based on Crystal); 500GB 850 M.2 (Data Drive; running at 523 based on Crystal)My Current PC:I Have an OLD i7-920, Overclocked at 4GHZ, 12GB DDR3 Ram; GTX 950 GPU, SSD (Non-RAID, running at 379, based on Crystal) Overall this PC might be worth $350.When you compare “SPECS vs SPECS” the NUC is the clear winner...Now here comes the Interesting thing... In terms of real life performance; My i7-920 outperformed the NUC by as much as 50%. Yes, I'm not kidding... And I’m not in drugs either… I even lowered the i7-920 CPU clock speed to 2.66GHZ (Non-overclocked speed) and it still outperformed the NUC. In a Windows load comparison, it took the NUC (With a PRO 950 running @ 2349) 9 seconds to load. The same test took my i7-920 a mere 5 seconds. Loading apps are also visibly faster on my 920. Visual Studio.net 2015 takes around 4 seconds to load in the NUC. It takes only 2 seconds to load in the i7-920. Don't forget that my 920 has a SSD running at 379 and LESS/SLOWER DDR3 RAM... Both PC were running a clean copy of Windows 10 PRO.In terms of GPU - my GTX 950 is far better than the IRIS 580. If I had to compare the IRIS 580 with a GTX, I would put it on par with the 650 or 750 in terms of performance. It's clear this isn’t a gamer's PC. Unless you are willing to spend an additional 800+ dollars on an external GPU and GPU Case.For around 1k, you could setup a Desktop PC with a i7-6700K @ 4GHZ, 16/32GB RAM, M.2 PRO, 2TB Mechanical HD, MID/HIGH Range GPU. A configuration like this, will far outperform the NUC and the i7-920 and will also cost around 1k (200 less than what I paid for the NUC and components).In My humble opinion, from a “High End PC User” that owns this product; I would not recommend that “Hardcore Gamer's” nor “High End Users” jump into to this bandwagon. Especially if you already have a PC that outperforms an i7-920. Jumping into the NUC would be taking a step backward in terms of performance and price.The NUC is a GREAT product. This is by FAR the BEST NUC out there. I own several 5th generation i5 NUC’s (One setup as media server and my wife also has one for personal use; She’s a non-IT person)If you don't already have a PC or have an old PC or a dual core PC and want to replace it. Perhaps this product is perfect for you. If you are a “High End User” or a “Hardcore Gamer” hoping to replace your high end desktop PC with a small factor NUC. This may not be it. For Hardcore gamer's this NUC might end up costing 2k (When you add the NUC, M.2, RAM, External GPU 970/980/1080, External GPU Enclosure, External Storage)I understand that you cannot compare a NUC with a laptop CPU to a desktop class CPU. But based on specs, the NUC should not have any issues in outperforming an OLD i7-920. Intel Should have installed a desktop class 6700k CPU or better or a BETTER mobile Quad core CPU with a lower IRIS GPU. This would have not been an issue for gamer's, since as it stands with the IRIS 580, hardcore gamer's will still need to install an external GPU to outperform their current high end systems. I’m assuming they did not go that route because of cost, heat and cooling.******************************UPDATE: 5/26/2016******************************I did some benchmark on the IRIS 580 and as expected it did not do well with high end games. I got between 7-12 FPS on Low Resolution playing Assassin's creed syndicate. I was not able to play the game at this FPS. It started "Ok" and then it got choppy until it stop.I also compared the NUC 6770HQ with an ASUS Laptop running 6700HQ (Same CPU, Different integrated GPU).  In terms of results, they are both pretty much the same in terms of benchmark. So as far of performance, this NUC falls short when compare to a desktop class CPU (i7-920 released on 2008).It is a GOOD PC, the BEST NUC out there, but not for High End Users nor Gamer's.******************************UPDATE: 6/01/2016******************************The NUC has some issues with heat. It runs HOT (80c - 90c) just by playing a Facebook game (Thunder Run: War of clans - @ level 44). This is a basic online game. It should handle it without any issues... So why the heat?  Even if you lower the performance mode in the BIOS to low, it still runs hot. In Idle most times runs at 50c-60c and 70c+ when using normal windows applications. In basic online games it jumps into the mid/upper 80's. At one point it hitting 93c.