What they do is, ensure for all type of assignments. But I asked them for a simulation file on hybrid grid, they told me to wait for 6 days for the solution. They also asked me do payment of $450 in advance. After 6 days they denied to give the solution as desired. Outputs were not up to the mark. I asked for rework, they did, but again I faced same problem with results, they were not accurate. Then I asked for my money back, but they refused. After so many requests, they only refunded $200. I lost my $250. They are cheaters.! At least if can't complete the assignments, then you should refund the money.