Thunderbolt SSD or USB 3 SSD - Need an external SSD drive I'm planing to get an SSD(500GB) probably Samsung EVO or Corsair(LS,LX,GT) &amp; seagate thunderbolt adapter for my macbook pros' 2011 and 2013 Retina. 
⌘ - I've already upgraded my 2011 MBP with Samsung EVO 250GB and it's performance is fantastic.

So here's my question -  Using SSD externally with thunderbolt worth it? both in terms of money and speed. 
My basic purpose of getting SSD for external use - 


Keep all my data (mostly movies), don't like keeping them on my laptop to eat space.
I travel a lot and never liked carrying those bulky Seagate goflex external hard drives, I'm more of a go bare 2.5 HDD guy because they are thin and small, unfortunately mechanical HDD's are fragile but SSD's aren't, they are already in a metal casing so all i need is an adapter to connect.



So should I go and get an SSD with thunderbolt adapter, will it deliver the same speed as the it delivers when placed internally? I'm open to getting an USB 3.0 adapter too (just to keep the cost low).

I'm aware of Lacie rugged thunderbolt SSD drive, honestly I don't like its life boat design. too bulky fatso! - - the max i want to use on SSD is a Silicon skin. 
So please do consider those bold face points while replying. thanks. It's my first post here.
i've looked at external SSD's for my mac as well. they seem to be pretty pricey for their purpose. Regards the speed, thunderbolt delivers about 10Gb/s which is plenty. it seems at least as fast as an internal SSD, and a heck a lot faster than USB 3.0. If you have to absolutley get an external SSD, get one that supports thunderbolt, or even better to get one that supports thunderbolt 2.0.