I think the extra $ to go filon w be well worth the saved time and reduced maint., ill go w that.
A good long term choice!
Rubber is all the rave these days...but only lasts 8-10 years in general, and when it starts leaking, if you don't notice it right away, much damage to your trailer is the result.
The "rubber roofs are the best thing since sliced bread" bit was started and continues by the RV industry who chose it because it is cheap $
There are builders who swear by it, and for them it is good.
As for the thousands of 10 to 15 year old used RV's out there with water damage because of failed rubber roofs, it isn't such a great thing.
Rob
Waiting for "someday" will leave you on your deathbed wondering why you didn't just rearrange your priorities and enjoy the time you had, instead of waiting for a "better" time to come along...