OK, you may be getting some conflicting info here on the poplar. First of all poplar is in the hardwood category, but it is not as hard as oak or maple for example. Poplar will not stand up to daily use as will harder hardwoods, especially if you wear shoes in your house. Also, poplar is difficult to stain and not get blotching, but on the other hand if you are going to stain it very dark, it probably doesn't matter. A quality top coat will be required, as it should be on any wood. No finish is bullet proof, the hardness of the wood will have a big impact on how long it lasts.