Far too many Nissan dealers for starters - if a ZED is going to traded in for another car at some point that garage will almost certainly be asking the local Nissan dealer for the trade-in price and if they see/hear the service book does not have Nissan dealer stamps I know from experience that will affect the price.
Also. while we know the good independents, non forum types will not know about Abbey ^^^ (as an example) and use that (or any other excuse) to drive down the trade-in price.
So I agree with
that's what I did and will do and is it turned out the Nissan HPC where I had my third service done just before the warranty expired agreed with me the gearbox was not right and Nissan agreed a new replacement box, so no hassles of otherwise having to go from an Indy to a Nissan dealer for the gearbox warranty claim.