I bought my Mog plate via an ad in Miscellany for a reasonably good price, my tin top plate through Regtransfers 20+ years ago at not such a reasonable price (though it is my initials and 3), and just bought SWMBO one through DVLA at a reasonable price. They were all easy to deal with and worked smoothly. One thing that did shock me was how little Regtransfers offered me when I had to get them valued (divorce settlement).