I have read some info on the Achilles on the Miata and drift forums. The initial impressions seem to be good. According to the manufacturer, they tried to match the Toyo R888 which is a great benchmark.
With the low pricing, it could be a great option especially if you aren't concerned with all out performance.
I cannot find the official specifications anywhere though. I would like to see the recommended psi range, min and max wheel widths and section width.