RAM: 4GB vs 8GB / Update: Resolved

Hey, Just hoping to get some advice.

Looking at a few new ultrabooks (mostly the Lenovo Yoga 13 at this point).

All other specs aside (i7, 256GB SSD), is there a noticeable difference between 4GB RAM vs 8GB RAM? The price difference on the BestBuy (USA) site is $200.

Will 4GB RAM be sufficient to last 5 years? I don't upgrade my laptops very often, need something that will last.

Thanks!

UPDATE:

Thanks to help from comments, my solution will likely be to get the config with the 4GB RAM, as it is much cheaper. It says on the Best Buy specs for this config that that system is upgradeable to 8GB RAM, so I have that option in the future.

Thanks!