Pragmatically - is there a big difference in finances (current or future) between you, & if so, who is richer? If you're marrying a Murdoch, you're unlikely to come away with anything worse than a broken heart, even if it does all fall apart. If you are significantly better off - then think very carefully. Broken hearts heal much quicker than savings, pensions and equity in a house, I'm afraid.
Marriage is best when it doesn't change your relationship much. I had no doubts when I married my DH, but a) we'd been together for decades and we're very happy b) I knew exactly why we were getting married - pensions and taxes!
Even in your 40s, it sounds like the shorter end of the typical time to the altar. It would be sensible to sit down and discuss finances, values, expectations, plans in grim detail - and get to know his family well - before actually marrying. And you say, "no kids expected" - if you are talking vasectomy or tied tubes or implant or Mirena, fair enough, but otherwise, people do sometimes have babies in their 40s, and not always planned...
The more planning, discussion and general due diligence you do now, the lighter your heart will be on your wedding day.