So I experienced last night my first enemy (4 man que).
The champions were with Mundo/Shen/Twisted Fate/Alistar. http://matchhistory.na.leagueoflegends.com/en/#match-details/NA1/2068141662/32434549?tab=overview (I barely won the game through mechanics in team fights/picking people late game)
I've seen some post about people foreseeing that 3-5 man que's will break solo que with their teamwork being amazing. Now that I've faced it personally I completely agree.
It's a problem. I felt like I was playing against a Ranked 5's Premade and it felt miserable that my allies weren't on the same page as me and my duo. The enemy was doing mundo tp under turret, alistar ult dive, and a tf ult on top of it bottom. 5 man ganks 10 minutes in.
I still won the game but I did not enjoy it at all. It felt miserable.