Thinking about getting a gaming laptop, any advice/opinions?

[so nice gamer]

Alright. So currently I'm using a pre-built, stock Acer Aspire S3 Ultrabook for most of what I do, including gaming. Building upon that, this thing is bordering right on the edge of meh, in terms of gaming ability, but it does everything else I need it to do just fine.

So, I'm deciding to save up money on the side (I'm in university, so I don't want to just abandon my hope of eating or having a home/car) for a nice, sleek gaming laptop. I was on the Toshiba site earlier today, looking at the Qosmio X870-BT3G23 gaming laptop (http://us.toshiba.com/computers/laptops/qosmio/X870/available-models). Also, I had been reading up online for which was better: pre-built or custom? (Consensus was custom). So, I went with the Qosmio above, and here's what I had selected (just a run through, no buying yet):
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Intel Core i7-3630QM Processor (6M Cache, up to 2.40 GHz)
Windows 8
12GB DDR3 1600MHz SDRAM (4GB + 4GB + 4GB)
256GB SSD (Solid State Disk, Serial ATA)
No Secondary Hard Drive Installed
3GB GDDR5 NVIDIA GeForce GTX 670M with Optimus Technology
Blu-ray Disc ROM with SuperMulti DVD±R/RW Double Layer drive
17.3" diagonal widescreen TFT LCD display at 1920 x 1080 native resolution (FHD)
Intel Wireless LAN (802.11b/g/n) + Intel Wireless Display Ready + Bluetooth v.4.0
Microsoft Office 1 month trial
Norton Internet Security Suite 2013 12-month subscription
1 Year Standard Warranty

+ Toshiba 18.4-inch Carrying Case

This came out to a total price of $1564.97.
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Now, this is where I'm curious as to what your advice/suggestions are.

Is there any better gaming laptops available for customization?
- And, if so, what sort of price difference should I expect? (Money is not an issue, as I'm setting aside a place for money to go towards this).
-- Also, is what I wrote above available for upgrades down the road? (Like, if I need/want a new graphics controller, can I do so?) or, is the better gaming laptop available for future upgrades? (If there turns out to be one.)

I'm not too knowledgeable when it comes down to computers, so I'd really appreciate any suggestions you may have.

Also, do you have any suggestions on peripherals (Mainly speakers.) and accessories (Such as fans and heatsinks.)?

Thanks for any and all help.

[Mugen]

I have Toshiba Qosmio F750 and i run most of my games medium - ultra settings like Skyrim, Hitman Absolution, Sleeping Dogs etc. but yours is very awesome laptop if you want more customization you can check ORIGIN PC they got very solid laptops.

http://www.originpc.com/