With release 2.9.0, OpenSolver adds integration with the commercial Satalia SolveEngine online solver. Satalia are at the early stages of their development, which will soon allow pay-per-hour access to the top commercial solvers from OpenSolver. These commercial solvers are, for some problems, much faster than the open source ones; this is particularly true for integer programmes (i.e. problems where the variables must be integer or binary valued).
You can subscribe to the Satalia service at https://solve.satalia.com/ Subscribing will give you a key that you enter into OpenSolver when using the SolverEngine.
We would welcome feedback from OpenSolver users on our trial of this new service.