The timing chain tensioner does not need to be change unless you have to. I asked Tom @ TGM about this and he has checked with Honda themselves regarding the tensioner. It is not neccessary on the major service to replace. I was in the same boat as the service manual suggested this but after talking it over with Tom, all is well.
I'd get the valves done. I done mine myself just 2 weeks ago ( double checking a tuners work really) and only took a couple hours and that was going back and forward between my garage and my shed for tools so should take someone who has done it a few times less time so isn't too expensive a job to do.
