When i try https://btcjam.com/api/v1/listings?appid=myappid&secret=mysecret, it response "500 server error"

No, never, i even can't sure pbmining is a company or a auto-working robot

if you buy new ghs today, and their miner didn't work since some accident, you cannot contact them, how to find your money back.

the key point is one month, they don't reply me in one month, so i guess they think ignore deceived man is ok, since they have get money,  they think find next stupid prey is only.thing they should do

in short
pbmining will never refund you
pbmining will never reply you anything after you paid

in detail
pbmining.com is scammer, cheat my 162.89 dollars, they will never reply your mail, here is my one-month mail list with pbmining https://gist.github.com/roroco/53c39d85f7e0e8e206f3,
here is my payment record https://blockchain.info/address/1Gr1CXm8VLhtT3q86rxfChA4D4PpC3WjaU.
remember if you wanna buy pbmining, if you have any question, they will never reply you, it just like pbmining only has a site but not human work on it

update:
attetion, it's not delay one day or one week, it's one month delay.

update
i contract them multi times in forum after sending refund mail, they didn't reply me.

update
the key point is not btc amount, they promise 5 years, but only site work well, are you really believe a robot site can work well 5 years? a possible result is their ghs doesn'r work in some day, you can'r contact them, and you will loss all your money

price: .0007 - .0008 btc/ghs(according btc price)
email: roorcodeath<at>@gmail.com

i have send a refund request to admin@pbmining.com about 5 hours, but pbmining.com never reply me anything.