You get so much better results when you buy flower and roll your own though. It seems like pre rolls generally use whatever scraps they had laying around. Also cones aren't that hard to roll, en mass even, all you have to do is invest in a cone filler. There's nothing wrong with smoking prerolls, but you will have better quality doing it yourself
Edit: another pro tip that will save you some hassle if you roll your own is to buy a coffee grinder just for your weed, pick out the big stems and grind 2-5 seconds in small bursts.