Roller chain breaking

I have a ride-on train that uses #25 roller chain twix the motor and drive shaft and continue to break the chain at the quick link.

Are there good-better-best types of chain?
Stainless steel?
Are there better quality quick links and retaining clips?
How about high grade steel chains?
Is it all Chinese made or is there better quality USA made chain?
What is the cost of your chain?
Is there a minimum order size?
What is the next size up from #-25?
Is that necessarily a stronger chain?
Do I have to change sprocket sizes then?
What are you recommendations for size chain for ride-on trains with 750 watt motor?