That is indeed a silly comparison. Compare stock SHIII to stock SHIV, and you'll easily see what already makes it a much better starting platform. That platform may not have ended up being used as thoroughly as SHIII with its mods (and honestly a big reason for that is that SHIII came out after a looooong drought of sub sims and instantly gathered the love and patience of a hungry hardcore community, and by the time SH4 came around many in that community had already sunk a lot of that energy into SHIII), but honestly, blow-for-blow... SH4+OM and SH3+GWX both have so much good to offer, that in the end comparison comes down not to objective features sets but pure personal preference. Both are equally easy to love, and both have things on each other that the other does not.
And then you have the whole pacific side, which SH3 certainly does not. And then there is already some other upstarts, including working versions of British and Russian submarines, with a Japanese campaign and WWI on the horizon. SHIV is a fantastic, flexible platform, and it's my hope that it keeps being built on. SHV also has promise, but I fear that the early dropping of patch support will make it very difficult for modders to flesh it out and shine it up...
And the 5-hour download is a silly excuse. OM/OMEGU is a measly quarter of the size of GWX, and you don't seem to have complaints about getting that ginormous mod, cause you know it's worth it
