Turner's Magic holds up really well considering what it is. I have been carrying a black walnut cigar pen finished with Turner's Magic for the last two years and the sheen hasn't noticeably diminished. My guess is a properly finished Turner's Magic finish will last through at least 3 years of daily use. It's important that you follow the directions and use the shellac sealer to fill in the pores before using the lacquer to achieve a high sheen.
For comparison, if the pen were finished with Hut Crystal Coat or other shellac/wax friction finish, the gloss or sheen would have lasted less than 1/2 a year.
Keep in mind that the best that Turner's Magic can achieve is a high sheen. Woodwrite's use of the "Super Gloss" label is highly misleading. It can never reach a shiny gloss the way Crystal Coat can. Still it will maintain that high sheen for a long time, whereas Crystal Coat will lose not only the initial high gloss, but also the high sheen in a matter of a few months.
I have not experience with Mylands.
Steve
