turntable mats: should I use one?

I've used a Reso-Mat on a highly modified VPI TNT and a Kenwood L07D. Both applications benefitted from a light clamping force or a record weight. I'm currently using a 1 lb. 6 oz. Still Points LPI record weight on top of Reso-Mat with a 4 lb. TT Weights copper mat underneath Reso-Mat. The LPI is about the right mass to couple an LP to the vinyl points with authority and get the best from Reso-Mat. I agree with Moonglum that without the added mass, Reso-Mat can sound a tad light and shimmery. But with moderate mass loading the presentation snaps into focus and gives a nice tight LF without bloat or false warmth.

Moonglum & Dave, Very well I will try the 233 g brass clamp again but if I remember correctly it doesn´t improve things because it may be too light with Reso-Mat.

Dear Dave & Harold,
Many thanks for the feedback. Looks like I may have been premature and unfair in my summation and perhaps should have tuned the Resomat a little? ;)

It may be that subconsciously I was thinking of the effects of offset centre hole drilling (which can be 2mm or more) meaning that the spikes would enter the actual playing area of the disc :O
This thought "creeps me out" slightly in the context of adding weights or clamps, even though I was fairly comfortable with the basic weight of the LP on the spikes.
;)

I know from experience that vinyl is a lot tougher than it looks. Have you seen any evidence of indents after applying pressure? (Dave?)

The one we supply for the Air Force One and Two turntables is quite outstanding, if I do say so myself... Please contact us for information and pricing.. - Bob Graham, Graham Engineering

Thanks Bob...sounds interesting. :)