I've never seen a situation where the return using points was near the reasonable value of those points for any cruise exchange whether it be MVC and only once with DVC. I've seen one exception with DVC, the initial AK offering where the offering was close to the going rental price.. Bluegreen gives a value per point and early on that value was modestly higher than the maintenance fees but those days are long gone. Even if one could find a situation where the numbers made sense, the other limitations are so negative that I would only consider it on short notice. Such an exchange is final, inflexible and comes with other gotcha's that detract further from the value. I'd only consider it if I had use or lose points that I didn't have a plan for anyway.
Are you referring to www.cruise-with-points.Marriott? We have used them and you can choose to either earn or use Bonvoy points by booking a cruise. We have chosen to earn points. They charge a booking fee of $24.99 and you earn 3x points plus 2x if you pay with a Marriott credit card. I have not looked at using Bonvoy points for a cruise, but as others have shared it probably isn’t a good value. At any rate they provide the same price for a cruise that one would get booking directly with a cruise line.
I'm a hands on planner but for cruises, I prefer to use a GOOD travel agent. Most don't charge extra, I'd avoid anyone that did. That way when you need something or the price changes, you can just let them know and they can do the work and spend the time making adjustments, dealing with with issues, etc. The prices will be the same but some of the companies may add additional options like On Board Credit or free gratuities. Costco will give you a rebate shopping card. The other thing that a TA can offer is access to group cruises which may be cheaper, even if you're not in the group. I found THIS WEBSITE helpful when looking at this issue lately since my usual TA has been promoted and will not longer be handling clients.
We USUALLY shop thru consolidators, like VTG- then we actually book direct. BUT last time- in March, VTG emailed a 'special' that was a suite at less than a high balcony cabin. Paula called Celebrity and suites were sold out. So we took the VTG offer. They threw in a modest OBC, a bottle of champagne, and premium drinks for the 11 nighter.
VTG is really great, especially if you have a good agent you have worked with over time. They know the ships, can recommend placement and other perks. And, of course, their website can't be beat. You can find everything there and if you want, use the information elsewhere, but we have liked them for many years and many trips.
For the big consolidators, the agents are mostly just phone reps where there may be high turnover. For a cruise like that you are probably better to find an independent agent that handles the smaller, more specialized lines, or book directly with the cruise line.
I checked a couple of the 90-day cruises on VTG for Royal Caribbean against the price for the same cruise on RC's web site. It is the same price on RC's as VTG. What, if any, is the benefit of booking on VTG versus directly through RC?