Both are great.
'98 Live Meltdown is an excellent representation of Priest live with Ripper, and proves they still have what it takes (as did their show at the Enmore).
Live Insurrection is great, but somewhat cleaned up, with the version of "The One You Love To Hate" patched together from rehearsals and soundchecks rather than in front of an audience. Not that I care that much when I listen to it...
Both Priest and Halford are now separate entities. Treat them as such, and enjoy both albums as such.