Just a story about the MO.
I tried to purchase two MOs ($999.3 each) on last Saturday. When the receipt came out, the second MO was voided, so the cashier gave me the first one with $1000 change. I suspected there might be something wrong with this trasaction, so I dicided to keep it until I can confirm it is outstanding. Unfortunately, I called to verify it yesterday and the system told me it was cashed on July.8 with the amount of $32.
Then I brought this MO to walmart and ask for a solution. They contacted with Moneygram and were told there are two records regarding this MO. After a long neogotiate with Moneygram finally I got a new one from Walmart today. I am lucky that a kind Walmart granny helped me solve this issue. If I did not verify this MO or keep the Walmart receipt, I can imagine probably I will lose $1000, plus a return check charge.

PS: The customer service of Moneygram is awful. One stupid rep even ask Walmart fax the cahsed MO to them... I had never seen the granny become angry before, but I did yesterday.