I will not vote for either in the NH primary in January 2016.
However, I will answer your question. If forced to choose, I would pick Romney because he’s a manager, and the ability to manage the Executive Branch has been sorely lacking for at least 20 years in an office which is designed as a managerial one.
I also take the dynastic issue seriously. And, I think the Bush Family is deceptive about their goals for the country, while with Romney, more or less, WYSIWYG. It is possible that Romney is not a transnationalist, it is certain that Bush is one.
Right now, I’m a Walker supporter. And, much against the trend here, I think a Senator who has not completed a single term with no executive track record should not be running for President. Think Harding, Kennedy, Obama.
I'm still waiting for the candidates to flesh out their positions... or for me to learn more about them... but if I had to vote right now, it would be for Walker. The track record in hostile territory cannot be denied.
So, you're not alone in going against the trend.
Why do people keep forgetting that Romney did win an election once, he was a disaster, he was incompetent, that is why he couldn’t be reelected and left office with 34%, and lost the seat to the democrats.