It's ok to have different guns from different manufacturers. Just buy the best of what each company makes if it fits your needs. FN may not have their pistols all debugged yet but they make a great rifle. I wouldn't pass up on a SCAR 17 because of a buggy FNX, the only person losing in that deal is you.
Dealing with a customer service rep on the phone can be a mixed bag with all of these companies, they aren't all knowledgeable on all the products. Look how long it took HK to improve their customer service reputation. As long as they actually handle the issue then that is all I care about, and it sounds like in this can FN did.