ROG Rampage V Extreme motherboard ("original" version, lol) and ROG Swift PG278Q monitor purchased late 2014. Both had some unadvertised "quirks" because (at the time) they were innovative, first-of-their-kind, early-adopter technologies. But, once the learning curve was complete and the tweaking/testing was completed and a few hidden glitches were properly corrected by firmware updates, everything worked even better than I initially promised or expected. The fan controllers built into my R5E mobo never delivered quite enough power when fully populated to the rated limits, but adding a fan-controller solved this problem for me forever and my (overclocked) mobo has never shown any other flaws. My Swift monitor was flawless out of the box and still remains flawless today. A number of other buyers complained about a variety of issues - like bad CPU sockets, bad VRMs, bad pixels, bad backlight bleeding, etc - on their ROG products at the time, but remember that these were very new and very cutting edge technologies and there's a price to be paid for
buying beta testing bleeding edge stuff.
I've now logged nearly 10,000 hours on my ROG motherboard and ROG monitors, they both continue to work flawlessly.
I've also got a ROG Router and that ridiculously useless (but really cool-looking) ROG OC Panel. Never any problems with either after all these years.
ASUS ROG-branded stuff is almost exactly the same as ASUS generic-branded stuff. Same robustly overengineered (and overkill) build quality, made in the same place by the same people, without any corner cutting. ASUS tech is well known for reliability, stability, and longevity.
ROG stuff has the black-and-blood theme and the boldly angular and aggressive style visually identifies the brand and apparently looks mean/cool enough to excite gamers.
ROG stuff has more "power", more VRMs, more tweaks and controls, more of everything possible to unlock and overclock every component possible.
ROG stuff has more features and add-ons which increase versatility, functionality, or compatibility beyond "normal" maximums.
In short, ROG is mostly a gaming brand which promises gaming performance. The highest-end and newest "flagship" ROG products always offer "innovative" (almost "experimental") ASUS inventions, technologies, and improvements which are primarily designed to make the system run games faster, better, and stabler than ever before. Mid- and lower-end ROG products tend to only implement the most successful of these technologies, they're targeted less to the enthusiasts and more to the powergaming masses.
Elite-tier ROG stuff arguably has less reliability, stability, and longevity than generic ASUS stuff - not because it's built cheaper but because it's built to push the limits, burn harder and hotter and faster - it tends to be more finicky and cantankerous and require tech savvy to properly configure. It also tends to break records and is often preferred by many "pro" overclockers. But it's admittedly not always the best choice for everyone, lol, most gamers would do better with stuff that "just works" when you turn it on (and thus the popularity of gaming consoles).
Common-tier ROG stuff is basically just the slightly-faster-slightly-more-awesomer "gamer optimized" version of normal ASUS stuff, very reliable, very stable, lasts a long time. From time to time you'll see ROG branding on "normal" ASUS stuff which is quite capable of gaming but makes no special attempt to improve gaming, it's brand swag without a sharp edge.
In my opinion: ASUS hardware is awesome, ASUS software is often decidedly mediocre, and much of the ASUS/ROG-specific software is sometimes overspecialized or downright useless. Fortunately, there's always many excellent free software alternatives available. ASUS usually offers updates, fixes, and revisions in a timely manner. ASUS support/RMA is very hit-or-miss, and it can vary substantially across different countries and regions. ASUS tends to be overpriced, ROG tends to be very expensive.
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