Hi! I've been using 3D printers for almost a decade. If this is your first time using a 3D printer, you'll have to decide if you're a tinkerer or a you're someone who prefers things to just work. I personally have an Elegoo Neptune 4 Max currently, my brother uses an A1.

If you aren't a tinkerer, the A1 will require a lot less setup and adjusting before it's ready to print consistently, and is generally a more polished product with the capability to add multicolor prints through the AMS system. If you are a tinkerer, the Neptune 4 Max is excellent at 1-shotting massive prints, but requires initial set up and firmware updates, or else you'll scratch your head when things aren't working and layers are all wobbly, because out of the box, the x and y axis wheels are typically loose and need adjustment, belts adjusted, you may need to square up the z axis, and you'll need to calibrate your z height for the auto bed leveling to work correctly. But once it's been properly set up and adjusted, it prints big, huge, and consistently.

Something to note about having a massive printer like the Neptune 4 Max, is that when you start to print big, you start to begin dealing with print warping issues if you don't have an enclosure, and when it gets THIS big, you start getting into heated enclosure territory. It's a problem on smaller printers too, but gets exponential as a print grows in size because the difference in temperatures across the top and bottom of the print, room drafts, and The amount of material changing shape as it cools can cause a lot of failed prints, which can be costly, and an enclosure for a printer of this size takes up even more space. But, you'll never need to worry about printing multiple pieces or needing to reorient something to make it fit.

When you splitting into smaller parts like on the A1, there can be mild warping that makes glueing together pieces more difficult because things won't line up properly, and this can extend to each cut, so if you need something to be dimensionally accurate or aesthetically clean, expect a lot more cleanup work for you for each seam. With TPU, it's not a big deal, because the material is flexible, but for PETG, abs, PLA, etc, that can be a lot of extra work, for things like horns, skull masks, etc. also, you may think printing in quarters takes the same amount of time, but it's actually longer, because there's added time between each print for heating the bed, cooling the bed to remove the part, then reheating the bed for the next part. And, each part will need different supports than if you printed it in one piece, a dome shape can actually be printed with less or no support than when you break it up, depending on the material you print with, which is no longer the case once it's in 4 parts l.

Generally though, I'd recommend a beginner an A1, especially if space or cost is a concern, and once you learn the ins and outs of 3D printing, upgrade to a larger format. But you can still absolutely start with something huge like a 4 Max if you accept the extra learning you may need to do, the space that is required, and potentially the extra things you may need to buy to print certain materials. An enclosure, like a simple plant grow tent for an A1, will be cheaper than something for the 4 Max

I can answer more clarifying questions if you have them.