Hate to say it but if it was me AND if I cared about Feng Shui, I'd stay away from both. It is such a gray area that you will always wonder. I know this is potentially in the far future but there is also the resale. If you are having this much issues with it, there are others who are in you predicament too. When selling, you've already eliminated a whole bunch of potential buyers.
How long has this house been on the market? If the seller is lucky, s/he will find a buyer who cares nothing about Feng Shui but I am sure the seller is already handicapped by the house location.
When it comes down to it, if you can live with the issue, then do it. If not, then reduce the stress and keep looking. Trying to find the fine print definition to rationalize the purchase might get you into the house but if it is as important to you (and your family) and it seems like it is, it will come back to bug you later on.
Just my .02. Good luck on the decision/search. :)