That's not damage to the guide. That's just some of the head casting that's chipped away after the original guide was drilled out of the head. It's not pretty, but it happens. It would have been better looking had the shop just cut that part of the original guide flush with the spring seat and run valve stem seals directly on the guides, but they didn't. Those new guides may not have been knurled. Most new guides are not smooth on the inside to allow oil to be retained for better lubrication. Most reputable shops don't knurl guides any longer as it is basically a band aid and doesn't last long at all. I would have them checked out and see just how much play there is in the guides and go from there.
