I'm not really certain of the value in a DCP player either,. Visually, it won't be replicating how it would look at a theater and just because it plays doesn't mean it will player on a real server. A better tool would be a compliance validator that would give you confidence a DCP was made correctly. I'm not saying there is no value in a DCP player, just not sure it's enough to justify the development time. Giving yourself time to test a DCP in the destination venue is the best, if possible.