I have an OLD Ryan trimmer that a coworker gave me because it didn't run. I got it running and it's a HORSE! It also has a blade attachment on it. It needs a lot more work before it sees daily duty though.
My daily-use trimmer is an ages-old Weed Eater brand. I've never had a Poulan product to treat me bad. This Weed Eater is at least a decade old. It's a GTI15 model -- they don't even make it anymore. It's so old, it's not even on their website, or in their database for user manuals, parts lists, etc.
You do get what you pay for, but that Featherlite trimmer SHOULD run right. Obviously, if they all ran like that, they wouldn't sell any of them. If you can't get it to run right, exchange it for a new one. If you only spent 100 bucks for it, you probably weren't comfortable spending any more for a "nicer" one. I'd do exactly the same thing. If my Weed Eater ever dies, I'll replace it with another Poulan product. True, they're not commercial quality, but they should last you decades if well-maintained and used in a residential environment.