Their opinions generally changed as time moved forward.

Originally, the general consensus among the victorious entente was that the Whites would win and a new, Democratic, semi-Federal Russia would emerge. Besides Poland, it was generally thought that most border states would be reincorporated.

So for a large portion of the Civil War, the Bolsheviks were generally underrated - regardless of the fact that the Whites were largely unpopular and disorganized, the Entente supported them for a large portion of the war. In fact, the Entente sent direct military aid to the White army. However as time dragged on Bolshevik success became more and more of a reality. The Western powers struggled with the idea, but some came more easily to it than others. Britain notably encouraged Poland to make peace with and recognize the Soviets not too long after the end of the civil war. This attitude was arguably formed by the Soviet's 'peace offensive,' following the defeat of the Whites - a large scale propaganda explosion.

The French were much more wary of the new Soviet republic - they notably advised the Poles "not to trust the words of the Soviets."

Source: Joseph Pilsudski, A European Federalist by M. K. Dziewanowski