Help please - how do SH3 and SH4 compare?

[MarkShot]

I've been playing AOD, SHCE, SC, and DW over the last couple of years.

I also played some SH3/GWX 1.03 over this past year.

When I got a new computer this year (March), I bought a copy of SH3/SH4. I didn't really bother with SH4. Now, it seems that SH4 is fairly mature and has received its final patch and has a large collection of mods.

So, I am thinking about 2008 and what I shall be playing.

I would like to ask how do SH3 and SH4 compare with each other? Perhaps, it would be better to ask how does SH3/GWX and SH4/mods compare, since I won't waste my time on the stock games?

Of course, I know that basics:

SH3 u-boats/German and the Atlantic/convoys. Very difficult to survive career. Less hardware demanding.

SH4 fleet boats/American and convoy/task forces. Easier to survive the war and better graphic engine. Other missions besides simply sink stuff.

* I have the hardware to run SH4 well. (Despite that I spent Christmas Day playing AOD under DOSBOX.)

This is all I know. Aside from the above what are differences in features provided the player and game play between the two games?

For SH3 these days, GWX has pretty much become the standard despite the availability of other mods.

Has SH4 reached this stage of mod standardization yet? Is there a single or just a few essential mod packages which I can install that contain the best of the modding which has been done since the game was released?

Thank you.