I have a chance to buy a pair of late model 115's for next to nothing, but they have 4,000 hours on them, are they worth rebuilding? should I just use them untill they just crap out? or forget the whole thing? I can get them for $2,000 for the pair (trade in offered) the dealer said he will just onsell them to a wrecker for parts, they are still running really well and have been serviced at Yamaha suggested intervals by a reputable dealer, is there any reason to buy them? and is a rebuild an option a them?