The free Xbox Series X and Xbox Series S upgrade for Marvel's Avengers arrived last week, and while the game itself has received somewhat of a lukewarm reception (to put it mildly), there's no doubt that this is a very, very good upgrade.

Eurogamer's Digital Foundry has performed an analysis on the two new Xbox versions and found that the quality mode, which targets native 4K rendering, is basically the same on Xbox Series X as it is on PlayStation 5, while the Xbox Series S has a 1440p target. And crucially, the 30fps "is essentially a lock on all systems."

The Xbox Series X and S versions also benefit from a performance mode which increases the frame rate to 60fps, and this is where the Xbox Series X outperforms the PS5, as "PS5 uses checkerboard rendering while Series X goes native."

"What this means is that the Sony platform can resolve higher pixel counts in like-for-like content thanks to its checkerboard solution, but for various reasons, Series X delivers a crisper picture."

"All together, PlayStation 5 in performance mode has more obvious image quality concessions that become more evident as the effects work scales up."

The downside on Xbox Series X compared to PS5 is slightly longer loading times, but we mean slightly. Digital Foundry says that a segment that took over a minute on PS4 Pro took four seconds on PS5, and six on Xbox Series X.

We've been playing a little bit of the Marvel's Avengers upgrade on Xbox Series X ourselves here at Pure Xbox, and can confirm that it looks fantastic in both quality and performance mode, and the loading times are almost non-existent. Regardless of your thoughts on the game itself right now, there's no doubt that this upgrade is very, very good.

"Ultimately, the Foundation Engine has never looked better - and it's great to see a significant amount of time and effort invested into these PS5 and Xbox Series conversions."

Have you tried the Marvel's Avengers upgrade on Xbox Series X yet? Let us know down below.