The job of a suit is to minimize the damage you receive when you fall off. All name brand suits will do that but, depending on the type and severity of the crash, they may be destroyed in the process. Unfortunately luck is a big factor on whether the suit can be used again. Did you land with all your weight on a seam? Was there a high point in the armour at a major point of contact? Did the suit shift? Did you catch a footpeg with your butt? (not pretty)
Although I personally know nothing about Langbros Leathers I do know that they don't have the experience of Alpinestars or Joe Rocket or Rev'it or any of the name brands. And that experience is what makes those companies build things a certain way. Even if you use the best materials, how a suit is designed and constructed is equally important.
You can build a nice looking suit but if you take short cuts on the way it's its constructed it might look similar but it's not going to protect as well when you crash.
When a name brand does find a problem, because they get feed back from hundreds, if not thousands, of crashes each year they either change their design or they go out of business. How big do you think Langbros R and D department is? I'm pretty sure they look at other peoples leathers and say to themselves "How can we make something that looks like that as cheaply and easily as possible?"
And if they get it wrong too often they just change their name and start over.
If you race you will fall, and when you do you will either be confirming that Alpinestars/Dianesse/REv'it/Tiachi/etc got it right or you're a beta tester for Langbros.
You're not betting your life on it but you are betting skin and bone.