It'll probably be fine. Note that generally when hard shell cases get "overloaded", i.e. it becomes really difficult to close the zip and/or the weight is very heavy, there is a greater chance that the case will crack due to adverse handling. This is why I prefer soft shell cases now; that said, if you aren't a heavy or bulky traveller, in general you would be fine.
Note that warranties will only cover inherent faults, i.e. faults that are a result of bad manufacturing, so the baggage was predisposed to fail. If the bag fails whilst on the road due to airline handling, most manufacturers and vendors will not cover that. You need to chase after the airline (or their handling representatives) and work out a process for repair or replacement.
Not many bags will survive if it gets treatment similar to a rugby ball during a World Cup grand final.