I don't have any personal experience and I'm not sure if I've seen reports about Tripster, either. At least not for quite a while.
The small print says this:
Can I cancel my tickets for a refund?
Tickets purchased through our site will list a cancellation/change policy on the voucher if it applies. The ticket can be canceled as long as they are within cancellation and have not been modified through Walt Disney Resort directly. Once modified, tickets are no longer refundable or cancelable, regardless the cancellation policy.
I would be concerned that the part I highlighted in red
could mean once attached to your
MDE account that is considered "modified."
And this:
Refund Policy
In the event of cancellation, and the cancellation occurred by the allowed cancellation date, the value of the resulting credit will be placed on your customer account. You may use that credit to make future bookings or, if your cancellation was less than 90 days from your original charge date, you may elect to receive a refund of your credit back to your original form of payment. Any unused credit will expire 24 months after the original charge date.
So I played around and got a date to "cancel for full refund" ranging from 1 day to 1 week prior; I'm not sure why the difference. Possibly because the 1-week prior was more than 90 days out, which puts the refund as an account credit.
I also noticed their website is showing savings of approx. $10 more than what I get comparing prices directly against the WDW website.
Note they only offer tickets through 2024.