Many cubers want to try a really big cube and there are many such cubes available in 2024. If you are wondering what the best 8x8? Or the best 9x9? Or the best 10x10? Or 11x11... Then the picture is very similar.
The best giant cubes are all from DianSheng, DianSheng have been working on a series of giant cubes which are magnetic for a few years and have released an 8x8 up to a 13x13 and 15x15, these perform very well and are definitely the best option. There are even ball core versions of the 8x8 and 9x9, although these may actually slow the puzzle down and not be worth it. The problem with the DianSheng big cubes is that they are very expensive.
There are 3 main cheaper options, the QiYi, MeiLong and YuXin Little Magic series, the prices for these are about the same for 8x8 to 11x11.
The YuXin Little Magic series provides big cubes which are all much bigger than the other options, they probably turn better than the QiYi and MeiLong series but are very large, their large size does make them look more impressive but it may be a bit more difficult to turn, especially for younger cubers.
The QiYi series is probably the best for most cubers due to its smaller size and stable structure, I have noticed some issues with the MeiLong series where the pieces break as they are a bit more fragile, this doesn't seem to happen with the QiYi big cubes. The QiYi big cubes are bigger than the DianSheng but are of a usable size.
It is important to remember with big cubes that there is always a risk of pops, especially if you keep them on loose tensions and have inaccurate turning. I recommend that you don't buy a big cube unless you are confident in your ability to reassemble a quarter of a 4x4.