So a few things i would like clarification on and would like to comment on:
That means we probably would only be able to use the
DVC once or twice a year.
DVC takes planning months in advance- this may be one negative for you if you tend to plan last minute, which in the DVC world is anything less than 7 months. To secure your time frame and room type you need to plan at least 7 months and definitely 11 months if you are looking at a busy DVC time (Sept - Jan).
It can save you money if you always stay at deluxe resorts, it can save you a little money or might be the same cost if you usually stay at moderate resorts and it will not save at all if you usually do values or stay off site. With that said - SSR typically is the best bang for your buck with a lower price per point and low yearly maintenance fees.
go at least once every month or other month usually staying at a resort.
If you mention which resorts it can probably give a better assessment of whether or not it is a good investment.
If you are not married i would be hesitant to get into a legally, financially binding contract such as this. It can make for a messy situation if in the future things do not work out for you. Of course it is hopeful that your relationship last. but as we all know sometimes things don't go as planned.
There is a lot to research and learn about DVC - there is some flexibility in DVC ownership, but it comes with the necessity to plan ahead. If you tend to change your trips last minute for some reason then DVC is not a good fit -- there are some restrictions if you are canceling within 30 or 60 days of your trip. Make sure you research this topic. It may make the decision for you.
Many people buy in with a smaller contract and then add on whether it be direct of resale so it isn't bad to start small and see how it works.
The positive of DVC is that it does have a good resale value, so if you did buy in and realized it doesn't really work for you, you could sell. But certainly best to research, learn about the product, play out the numbers and see if it would work for your needs all while saving you a little money.
Ask lots of questions here -- it can help to receive some different input and perspectives that you may not have even thought of.