Slim Armor isn't slim, but still doesn't impair my day-to-day activity... it definitely has a lot of thickness... if you like your phone naked best, you'll definitely hate Slim Armor... The only thing that's slim on Slim Armor is the name...

I haven't try dropping my phone (and I don't want to) but I'm pretty confident with the protection...

I only has Slim Armor, so I do not know about others...

but iinm, all Spigen's case actually significantly thick... some might be not as thick as my Slim Armor, or maybe Tough Armor but they still add considerable thickness to your phone...

Sorry for taking so long to answer...

I'm using the 2nd gen X-One... though I won't recommend that... worms/wrinkles, heck even bubbles appears after months of using it... too expensive for a suck film... go for something else