I would not treat 1.0 USD as equal to 0.63 GBP. In order to check for equality of monitary value, you'd need more information than just the two values - you'd also need the current exchange rate, etc. This is especially true, as the same two values won't be equal consistently, and equality should always be true if the two values are ever equal.
As such, a method, such as AreEquivalentMonitaryValues()
, seems appropriate - especially given that extra info is required.