1. Food - if you are on the road, you're gonna get paid decently to eat! You may get a per diem, or allowed to expense "at cost." This is a HUGE cost savings for most people and you'll be eating very good. You will get sick of nice restaurants!
2. Miles and Points: You travel like crazy, you get points like crazy. You won't be buying any airline tickets for personal travel for a long time and you will be staying in nice hotels for free with all those points. Get a credit card that rewards with points, and you'll be getting points for all those meals you expense too. Oh, and rental cars and ... you get the point.
3. You get to see a wide variety of people and tech challenges. This is good. Think of it as "technical culture" -- much like world travelers, but for tech systems.
This list could go on for a while, but those are the major advantages. Don't be fooled though! Disadvantages are many. It's hard living this kind of life. It gets old and I think it ages people prematurely.
Don't let it factor down to a money thing. Let if factor down to what you really want.
I know which business model I prefer, but not sure if that translates to which company I would rather work for. Given all the extra time travelling (and lifestyle restrictions / hardships which go with travelling,) it's possible the product development firm actually pays more for your time.
The travel will be fun, but you'll have little opportunity to build a home life or deep personal relationships.
You can take a product development job anytime, but consulting and 100% travel are only doable for a brief window in your life (typically when you don't have a wife/husband and kids). If you're ok with the travel, give the consulting gig a try. You can always go back to civilian life later.
But I suspect this is not the only trade-off you need to be thinking about. Which one brings you more career development or puts on the path you want to be on? Which company has people you would enjoy working with more? Which one has a better culture?
Even on the money front, would working for the product dev firm be a short term lost revenue but in 1-2 years you would be earning a lot more?