Linn LP12 vs Thoren TD350

I currently own a nice Linn LP12 with lingo powersupply, a Naim Aro tonearm and a built in Naim phono/pre with hicap power supply. In the opinion of the analog nuts out there, would a Thorens TD 350 with an SME M2 tonearm be an upgrade, a downgrade, lateral or just good but differnt. Going to the Thorens would also require the purchase of a new phono pre.

Rest of system ins C-j, Marantz and B&W. Music taste is varied from Andy Williams to country to Led Zep.

I am satisfied with the sound of my system, but like many, get restless.

Thanks for your input.
Regards,
Paul