Minimize Packet Loss effect between two sites

We had our main office in HK and two branch offices in China. Our China users are using Citrix from HK site, through Internet access.

Recently, we found that the packet loss issue between HK sites to China sites greatly effect the Citrix Performance.

We are thinking the following setup:
HK Site:
Two broadband with different ISP

China site:
Two broadband with different ISP

Can PepLink help in our situation to build up the VPN for the sites?

Also, how can PepLink handle the packet loss? At what level of Packet loss can the VPN built by PepLink substain without broken?