I took my 2011 RRS Supercharged with 97K miles into a local indy shop here in No. VA that seems to be pretty reputable. They know all about the timing chain guide issue on the early Ford 5.0 V8's - in fact they had a LR4 sitting in front of the shop they had just completed the service on. I don't have any CEL illuminated but I can hear the increased noise on the timing chain and I feel a pre-emptive service will avoid longer term costs down the road. They quoted $6K for the service, possibly a little more if they supercharger needs any work. I'd like to keep the car operational for a long time so it seems like the right thing to do. I've looked at the zip tie bulletin and I feel I could do that - doesn't seem too much more complicated than the timing belt service I've done on my 928. But this engine is a lot more complicated and I feel a professional shop would be the safer route. Does this cost seem in line with what others have paid independent shops? Has anyone done their own timing chain guide replacement and feel that was a better route?