Those absolutely insane file sizes don't benefit anyone; all you're doing is wasting server space and negatively affecting the distribution of the original files. I know the first thing I do after downloading something like this is extract the files, downsize them and immediately delete the zip, unlike reasonably sized files which I'm still seeding years after getting them.
The funny thing is that, If you were really that worried about the quality, you wouldn't be using JPG in the first place but PNG, which is a lossless format. The funniest thing is that the site automatically converts the images to 500-700 kB files anyways, so that's what the majority of people are going to see, and even that is more than enough to see every detail in the drawings.
On one hand, resolution is higher, which is fine, as you can download the downsampled archive or files instead (EH automatically provides a number of downsample ranges). That means this SHOULD be the superior one. On the other hand, >300 dpi is explicitly listed as "excessive" in the rules, and this is 600, making its validity as an upload slightly muddier to my mind. We'll see.