Inov-8 continues to, well, innovate in the space of ultra-durable, trail-tested footwear. Utilizing their proprietary graphene-infused mid and outsole, they developed the RocFly G 390 to crush the competition within the lightweight hiking boot niche.
This model was worn by Inov-8 ambassador James Forrest when he set the self-supported Fastest Known Time on a 500-mile hike of Great Britain’s National Three Peaks and so it was only natural that we gave them a spin to see if they’re as good as they seem.
The Inov-8 RocFly G 390 At-a-Glance
Weight: 390g / 13.75oz (each)
Sole: GRAPHENE-GRIP™ outsole
Stack height: 25mm heel / 19mm forefoot
Material: Breathable knit upper
Circumstances of Use
I put these through their paces on day hikes and trail runs in cool, partially snowy conditions on trails within a well-used park. The terrain was mostly gravel roadways, tarmac roads, and wooded trails.
I normally hike and run in Topo Athletic shoes like the Ultraventure and MTN Racer, which boast similar stack heights and durability claims, and was excited to see how these would compare.
GRAPHENE-GRIP™ rubber. Delivers the world’s toughest grip—insanely sticky traction AND increased durability with no compromise. 50% stronger, 50% more elastic, 50% harder wearing—all extending the life of the outsole.
G-FLY™ Foam. Graphene-enhanced foam retains its optimal levels of cushioned thickness and snappy energy return for longer, helping long-distance hikers feel fresher over greater distances.
ADAPTER-FLEX™ groove. The 10mm deep groove allows the boot to adapt, react, and mold to uneven terrain for a responsive, agile feel that is free of rigidity but full of cushioning.
Rocfly G 390 Pros
Fit and Feel. Inov-8 uses a scale of 1-5 to indicate how wide the toebox is, as it differs from one model to another. The RocFly G 390s have a five, meaning it’s the widest version offered, and the fit was fantastic. I found that they were true-to-size and did not require sizing up to achieve optimal fit. I took them on an eight-mile trail/hike right out of the box and they felt great right away with no break-in required.
Though closely related to fit, feel is more about how the shoe works long-term. As soon as I put these on, it felt like they molded to my feet like a pair of old slippers. The uppers are a knit material that is flexible and porous, which allows for superior breathability and adaptation to your feet as they swell over long efforts or thru-hikes. Though I hadn’t originally intended on running with them, they felt so good and light that I decided to try it out. I was not at all bothered by extra ankle support.
Features. The GRAPHENE-GRIP™ technology is no joke. With large, spaced-out lugs I felt completely secure walking over wet rock and slick roots. The graphene-enhanced midsole foam is a relatively new feature that Inov-8 claims is “scientifically proven to deliver 25% greater energy return and retain its optimum levels of underfoot rebound and cushioning for longer.” While I don’t have any data on that in particular, I can attest to the fact that the midsole does not feel deflated and sloppy after the first few miles, as is often the case for less-durable trail runners (looking at you, Altra).
Durability. It may be too early to call at this point, but based on other reviews we’ve done and my testing, which has left them looking brand-new, I am willing to bet these will last longer than any other shoe in my closet. The Graphene grip just won’t quit and wears like iron, which fully supports their claims.
Rocfly G 390 Cons
Price & Availability. The elephant in the room with these is their price point. At more than $200 per pair, they are significantly more expensive than any trail runner on the market and quite a bit more than comparable hiking boots as well. Though hard to swallow, they will likely last at least 50% longer than other options and may be worth the investment, especially if you can find them on sale.
Also, Inov-8 is a brand based in the UK and so they can occasionally be hard to find. Though often available through retailers like REI and Backcountry, the size and model options tend to be limited.
Limited Use. While not a drawback for all, there are certain circumstances in which the RocFlys are not a good choice. These shoes are great on rocky, rooty, rugged, and wet trails such as those found in New England. However, they’re less appropriate for hot, dry, and desert areas such as California, Utah, or Nevada. This is because the knit upper is much too permeable and will allow in sand and other debris which can cause blisters and other foot issues.
There’s a reason Inov-8 was selected as one of the best trail runners for thru-hiking in 2021, receiving accolades for their durability, grip, and fit. The company has continued its trend of innovation and expansion of offerings that include Graphene technology. As a result, the RocFly G 390s are very impressive.
Though many thru-hikers tout the benefits of trail runners, not everyone is comfortable making the switch and ditching their boots. If you hike in areas that are wet and rugged and are more comfortable with a higher level of ankle support with incredible durability, these may be the perfect choice for you—as long as you can stomach the price.
Weight: 13 ounces
Drop: 5 mm
Weight: 11.5 ounces
Weight: 16 ounces
Drop: 5 mm
The Inov-8 Rocfly G 390 was donated for purpose of review.
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