SP10mk2: OMA Graphite plinth vs.Dobbins plinth


According to the price lists they are in one category, but anyone could comment on quality/performance? At the moment i use big Teak Wood plinth (just $750) custom made in Taiwan for my SP10mk2. Looking for upgrade in the future. I use my sp10mk2 with Reed "12 tonearm now. Doest the plinth actually makes a big difference in sound? My stand is well damped with glass, metal and sarbothane in between.

1) Oswald Mill Audio graphite slate plinth (single layer) $2750, double layer looks fantastic but cost $3500

2) Steve Dobbins famous custom plinth cost $2650 including three Stillpoints feet and automotive show quality paint in black or white. Design has changed many times, still hard to find any current plinth picture online.

I know there are Albert Porter's and Artisan Fidelity quality plinth available, but i don't like the design (i mean just how it looks) for SP10.
128x128chakster
Has anyone tried upgrading the power cord of the SP-10 mk2 power supply ? It comes with a thin captive lead. Changing it needs some work. Before I try that I would like to ensure that it really brings an improvement
@pani A reliable audiophile friend of mine installed an IEC inlet in the SP-10 Mk2 PS and tried several high end PCs.  No difference.
That company is USA offering many different solution to clean metal (guns, knifes etc), i think some stuff works well for metal parts of the turntables etc 
Has anyone tried upgrading the power cord of the SP-10 mk2 power supply ?

I did it on the power supplies of my SP 10 but I have to complete the restoration and I do not know yet if the sound could miglorate.

I have not used IEC sockets because I want to keep my power supplies as original as possible, the only cable that is quite compatible with the original power supply hole is the VDH Mainserver; I had to widen the fairlead and work a little for the passage but I did it.

Here

The VDH is deprived of the cladding under the transformer to make the internal cables reach the terminals.