I just bought a fish from them. It went well. here are my details/thoughts:
1) Their website is legit, secure, you can use paypal, etc, so that is good
2) Website does not say where they are located, so I thought that was strange at first
3) one of the stipulations for getting a credit t for DOI is that you have to send a pic of the shipping box with some sort of damage. I think this is a crappy stipulation. Presumably it is there so that the blame can go on the company delivering the item and not on the shipper.
So, considering #2&3 above I emailed them, but got zero response. So that is lame in my opinion.
So then I yelled yolo and ordered a 5-6" serrasalmus geryi anyway..
Everything was fine after that. Fish was shipped out within a few days and arrived well packaged and in good shape. The fish was as advertised: about 5" SL and 6" TL, and looked healthy and was active in my tank right away. Additionally, it was not all skinny like most of the Ps I've gotten via mail order over the years.
I would buy again.
Pics from first day:
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Cheers!