I'm sure Sportcheck and Walmart bikes are fine if you or someone you know is able to go over the bike and make sure everything has been assembled properly. I just wouldn't trust them without a 2nd set of eyes to go over the bike.
Bicycle Repair Hub posts photos of bikes on Facebook from Walmart and Sportchek that have been assembled incorrectly.
He posted this one earlier this week. Most people wouldn't even notice something was wrong with this bike. (the fork is backwards)
