Laptop Dilemma

Greetings community,

I throw myself on your mercy, and realize that there are many who may be frustrated by the ignorance of my question, but I am seeking to purchase a decent laptop in the very near future. I have shopped around as best I can and came up with two builds I like but with very different prices.

They have virtually identical stats, from processor to ram to hard drive to video card, with one key difference:
One is entirely DDR2 & one is DDR3 across the board.

The difference in prices is $1173 and $1549.

My question is: Is DDR3 worth the price difference of $400?

I genuinely don't know.

I appreciate any feedback and help provided.

Sincerely,
Lappybuyer