i've recently talked to a lot of breeders (as we're planning to breed) that get their breeder pairs from thailand off ab .. and there are a lot of horror stories on the forums and a lot of complaints on ab .. almost all thai breeders that post on aqua bid have a warning regarding tailbiting and they do not replace if fish have torn fins on arrival
plakats fall under the 20% .. and i don't know what you mean by hm's are the ones that tail bite .. none of my hm have ever nipped or taken a bite out of their fins .. only my veilteils bite .. tailbiting is not based on what type of betta tail you have .. some bettas will do it .. some won't .. generalizing by saying hm's bite more is just what people say based on their own experience .. there's no science behind that statement
Let me rephrase. The only bettas I've ever heard of tailbiting during shipping are halfmoons, and halfmoons and bettas like them (deltas etc) are the most frequent biters. Tail biting has to do with stress from shipping, not breeders. Why would they replace a fish for tail biting? Tails grow back and shipping any fish that far has some risks associated with it. One of the main trans-shippers in the US has less than 12 DOA fish a year, and gets hundreds imported to her. It just sounds like you're trying to scare someone off saying all fish tail bite in shipping when it is really only a few, not 80% or anywhere close to that, and doesn't apply at all to females or certain tail types. You're saying every single fish who is long finned will tail bite if you're saying the 20% who don't are short-finned fish, and that's just not true and the OP should know that. I'm curious as to how many fish of different tail types you have imported and which of those fish have had issues, but that's not relevant here.
To the OP and point of this thread:
My previous post explains how AB works. If you want to see how satisfied customers have been with the breeder, click the number next to their name. Example - XYZBetta (46/46) XYZBetta is the username, and the 46/46 lets you know that all 46 customers gave positive feedback. You can click the number to see written feedback as well. Some breeders have thousands of customers, every one satisfied.
Your best bet and my best advice: Create your account and shop around frequently online to know you're getting a good deal. Email the breeder about the fish you're interested in, establishing a relationship can get you wonderful discounts and access to fish before they are posted to the general site. You can also get access to the genetic background of your fish, information about that breeder, and get tips and information from them about diet/breeding/etc. If you buy a fish that is already in the US, your costs will be lower. There are a few US breeders on AB, as well as many people in the US who import bettas from oversees and then sell extras.