it's not a bad thing sometimes breeders have problems with males and females that are young and don't "know how to breed". sometimes it takes a few trys for them to get it right. having a pair that have bred before (as long as they aren't too old) makes it easier the next time round.
Yikes, that's a tough female if all that fin damage was from the spawn, Lol. Be aware his fins may never grow back "right". But I'll back up BKK (not that BKK needs any backing up, hehe) that there is nothing bad about Bettas that have already spawned. He's probably pointing this out for 2 reasons, the fin damage on the male (to explain it) and if someone is looking for a breeding pair, these ones are proven. Since they're still only 5 months you'll have no problem with them being too old (for breeding or being a pet). So if you like them, go for it.