I'm generally not a fan of remakes/remasters that do essentially nothing but change the artstyle for no reason. Yet, despite some unfortunate missteps (W6-3 in SMB1 and many W8 levels in SMB3 are no longer monochrome), I do actually prefer the aesthetics here. The arranged music by Soyo Oka is excellent as well.

The only real flaw for me is how the brick physics work in SMB1/LL. In All-Stars, hitting a brick block as Super or Fire Mario will cause you to jump through it instead of rebounding. It's not game-changing, but it feels a bit awkward and forces you to wait longer before hitting more blocks. Luckily, there's a patch that fixes this. There's another patch that restores SMB3's Famicom difficulty, where getting hit while powered-up always reverts you to Small - highly recommended. These patches work with both All-Stars and All-Stars + SMW.

Ultimately a pointless remake, but nonetheless my preferred way of playing the original Mario games.

I hesitate to put this at a 5 star rating purely because this isn't the optimal way to play some of these games. I'm primarily referring to the Advance series on GBA; Super Mario Bros 2 and 3 both have better versions from those series. With this being said, I would be remiss to say that even today, this collection maintains a ton of value and is a must-play for any platformer fan.
3/4 of these (more on that in a second 👀) are classics on their own, but this remake gives them all an additional level of polish. The visual adjustments are the most noticeable and welcome change of them all- while the archaic 8-bit graphics of the originals are charming, the All-Stars renovation really cements the games as timeless. Super Mario Bros and the Lost Levels really saw the most improvement in this regard, the new visuals have so much more personality and are much more vibrant. Speaking of the Lost Levels though, it really sticks out compared to the rest of the titles, it's honestly kind of utter dogshit. I see it as more of a bonus though, because the other 3 games are brilliant and endlessly replayable.

It's a little embarrassing to admit that I never played this on original hardware. My first playthrough was the Wii version, and my most recent was via Nintendo Switch Online. No matter what you play it on I highly recommend it though

Maybe the definitive version of all of these games? That's up for debate certainly, but there is more then just the standard graphical improvements here; these are full blown overhauls, maybe some of the earliest Nintendo did, and the QOL changes that they do make all of the difference. Super Mario Bros. 1 in particular feels like a completely new experience while retaining that game's unique individual quirks, which is not an easy feat.

There isn't a whole lot I can say about this that hasn't already been said in my other write ups for these games - all stills classics across the board - but honestly if you are going to play 2D Mario this might be your best introduction. A clear, unfiltered view of how timeless these particular installments are while giving you a better experience then the originals. One of my personal favourite compilation titles, well worth getting.