We've used the 11880 since they were introduced on the market and are very happy with the results we're getting. We do quite a lot of canvas prints, mostly art reproductions. Our customers are very demanding regarding color and we are able to get results that are very close to the original. It is only when we have art with very vivid red colors that our 9900 is better.
Regarding longevity, your best bet is Wilhelm Research. They have published years before noticeable fading for some canvas materials. You should check how much the printer has been used. You can do this if you print a nozzle check. There you will see if all the nozzles are OK, but also how many meters that the printer has printed.
Stefan