SME 309 vs SME IV - sonic differences?

Stereophile did a review a while back. I believe Fremer compared the 310 arm on a SME 10 table. I think it's posted on their website. Look under turntables...He did notice in improvement between the 310 and the IV.Vi.

The IV.Vi has a few differences over the IV you are asking about. The IV.Vi has the same abec bearings as a SME V and different internal wiring from a 309 or a V. The IV.Vi uses Magnan copper ribbon wire internally. Also the IV.Vi has the damping trough as standard, option on the 309 series.

I use a IV.Vi, it's a damn good arm. I am sure a Graham or Triplanar are better, but more $$'s.

Looking at your system, I'd try and go for a IV.Vi or a V. No use skimping here. Not sure what arm you have right now. Also, if you have a 309 today (I am guessing here) have you tried better arm cables? They make a huge difference on SME arms. Whether it's a 309 or a IV, V...

I had a 345 (basically a 309) and a V. I didnt hear a big difference between them using a high resolution cartridge ( ca insider ) and clean phonopre ( custom tube ) The removable headshell is very convienient on the 309 and I preffered using that arm and never missed the performance difference of the V.
my $.02 Rick

I currently own a modified RB300 (Kerry counterweight / Incognito rewire) - I am receiving various recommendations pointing to Morch as a good option as well - goshhh this is though!

Thanks so far for your feedback.