Is this good for TS3 with all expansions, stuff packs, and lots of store content (especially the graphics card)?

Processor : 4th Generation Intel Core i7-4710HQ Processor (2.50GHz 1600MHz 6MB)
Memory : 8.0GB PC3-12800 DDR3L SDRAM 1600 MHz
Graphics : NVIDIA GeForce GTX 860M 2GB

With TS3 it's never overkill. My specs are roughly similiar to that, and while my game runs relatively well it's not exactly a smooth 40 FPS.

That's actually pretty high even for TS3. But considering the bugs that game has, no processor or graphic card can fix that. My advice is to install all of TS3 games you want and then install on of these mods (but only one!):

http://nraas.wikispaces.com/MasterController - Twallan's MasterController

or

http://www.moreawesomethanyou.com/s...ic,15185.0.html - AwesomeMod

i7 is really good, so yes

Yes, it is adequate. More than adequate. It is also not exactly a budget model you're getting. Therefore, if you really want a high end laptop, I might make the following suggestion if you can swing just a little more money (I know, it's a freaking fortune already, but we're talking high end performance here). That 860M is a mobile version of an Nvidia 860 chip. While quite good, it is throttled back to reduce power drain and heat generation, and is not really running like a "860 desktop" graphics card does.

However, Nvidia just came out with the 970M and 980M mobile chips. These are derived from their now top of the line 970GTX-980GTX cards for desktops. They are also the first mobile chips from anyone which come close to matching their desktop counterpart, and are still energy efficient. The chip is already available in laptops from folks like ASUS, MSI, and Maingear (who I love, and are my newest fave boutique builders right now). IF you could swing it, going for a 9xxM chip will give you the best gaming experience you'll likely ever get in a laptop, and probably future proof you for a few years, especially if you play games other than just TS3 on it. Is it NECESSARY? No, of course not. But at the price point you're already looking at, it makes sense to get the newer, and in this case, way better performing graphics chipset. After all, laptop graphics can't be easily upgraded , if at all, unlike a desktop where you can go with a step down in graphics card, and swap it out for something higher end down the road.

Oh, I'm very aware. However, having gone from 4 gigs of RAM to 8 recently I did notice a slight increase in performance - loading times, mostly. I'm running on the highest settings with a HQ mod, custom lighting and tweaked LODs...on top of that I use NRaas DebugEnabler, Dresser, ErrorTrap and a few others...10 EPs, 4 SPs, some store content, some CC...that's really the point where 4 gigs is your bare minimum, and only now that I've upgraded I can leave Chrome running in the background without massive lagging issues.

As a 32 bit program, TS3 theoretically cannot access more than 4 GB of RAM. Practically, I've found it becomes unstable with a 3.2 to definitely unstable with 3.5 GB footprint (typically, Error 12s when saving, and flat out CTDs just when you don't want them). However, while the program can access only 4 GB (for ease of discussion), your system still needs "room" for your OS and background processes. So if you're playing with only 4 GB of RAM total, the game cannot even access the normal maximum memory space of 3.2 GB. However, if you have a 64 bit OS, and let's face it, most folks do these days, adding additional RAM, such as you did going from 4 to 8, now allows for sufficient memory space for the OS to run, background stuff to run, and in your case Google Chrome, all while still handling your modded TS3 game, HQ mod and others included.

Although, TBH, I prefer running the game in full screen mode for immersion, alt tabbing out if I need to do something else, and despite having 16 GB installed. I also keep the background stuff pretty quiet when I'm playing. Sometimes background processes can cause game "stumbles", irrespective of available memory, such as some automated update to a program that steps on TS3's toes.