At first, I thought liqui was scam too. Once I sent 1 eth instead of 1 mgo to MGO wallet just to test it.
After long conversations they finally returned my 1 eth back. Though it took too long to wait
for their replies, they didn't cheat and fulfill their obligations.
I used Liqui a few times, did not run into problems.
It seems like Poloniex, Bittrex and Liqui have a lot of complaints in their topics right now.
It seems they can't handle all the fresh money flowing in and need more support members.