The 8300 is not a good sheet machine. Large sheets are forced into an almost 180 degree curve over about 18" of length, and for whatever reason my 8300 can't print about 2" of 8.5 x 11" sheets. And I don't care, I don't see the sense of using sheets when rolls are available at better pricing and are easier to use. My $0 decurler does a perfect job in almost no time at all.
I now have more square meters run through my 8300 than all my previous Epsons combined. I am a relatively high volume user and I have to say the 8300 has given me so few problems relative to my old Epsons that it is by comparison problem-free. It's hard to convey the ecsctatic joy I felt at the loss of those almost daily S&M sessions spent kneeling before Mistresses 9880, paper towels and potions in hand, begging her to please unclog her little nozzles. The 8300 is just a good natured ol' gal who'll put up with almost anything.
I have replaced a few heads, all sent to me at no charge overnight. I have spent $0 on maintenance, other than the very small amount of ink and 30 minutes of time used during head changes. I have performed no other maintenance beyond cleaning the suction ports and very occasionally replacing the maintenance tank. The only time I even bother to print head checks is before and after printing profile targets, and I have never been disappointed with what I saw. All this from a printer that is close enough to my canvas spraying area that I have to wipe overspray dust off its horizontal surfaces once in a while. This may or may not be a typical experience, and perhaps I'm lucky. After all, for any printer we mostly only hear from those who are suffering, so take that into consideration, too.
My attitude towards warranties is this: if something goes wrong that I can't fix myself, I'll just hit the Reset Button and buy a new damned printer and breathe easy for another 2 years, at least. Right now the money I would have spent on warranties is in the bank and will go a long way towards a new 9400 when I move my shop this summer.
But maybe very low volume use indicates that a printing service would be a better choice for you. If there's a good, pro quality printer in your area it might be worthwhile spread-sheeting the options. Big printers of every type are first and foremost production machines, with the 3880 being the jumping off point.