Hi, i dont think that is a lot of hours, and i dont think the unit will lose capacity or preformance just from having beein used a lot. my 898 is now close to 600 hours and i think it oreforms better, with its updates and my understanding of how to read the images. :-) as lo.g as the unit looks good and has been in good care i don think the hours matter for anythhing else than telling you how much time you soend on the water. :-)