What tonearm is recommended for the denon 103r

The best I heard was on my Ikeda 407 for the 103r. It did sound surprisingly decent.  And I’m sure other expensive high mass arms are nice to. But I would never restrict my expensive arm to a cheap cartridge. With my FR64fx and Basis vector the denon  wasn’t as smooth or refined sounding. As someone stated already, the 103d, I had one in the 80’s and really liked it. I can’t remember the arm, it was not an expensive arm and was lower mass. It was on an Ariston table, similar to the Linn Sondek. This would be a better choice. Buying a 103 in my opinion is for budget reasons so the arm is going to be budget too or just get a better cartridge. I get the whole idea with getting a cheap cartridge to sound good is fun but there not so cheap anymore. I bought 2 about 5 years ago for $275 each including shipping. Quite a bit more pricey now. Still have one with about 15 hours on it. I find for a single cartridge owner it’s too expensive to get these to perform good that there’s better choices to be made. 

I got the DL103R up and running on my SME-V, Garrard 301. It sounds nice. I have some optimisations left to do. I need to open up my phono stage and change the gain setting (ART9 was 0.5mv whereas 103R is 0.25mv), i need to finetune the pivot to stylus distance (i have assumed it is unchanged since I screwed back the arm on the board with no change to position), adjust VTA and finally run in the cartridge. I can manipulate the loading through 6 settings in the phono. I think over the next month all these upsides should roll in and enable me to reach close to where the ART-9 was.

I usually see the DL103R matched with a high mass tonearm due to it being a low compliance cartridge, the SME V seems to be on the lighter side. I'm glad it's working out for you though.

I have finished all optimizations. In my system, the ART-9 had a modest edge over my Marantz SA10 for most recordings that were done recently (e.g. some recent 24-192 productions like Miles Davis Kind of Blue, and In a Silent Way etc.). The DL103R maintains the same edge. I have managed to extract a bit more from it than I could from ART-9 by changing cartridge loading to a higher 300 Ohms. I have however the suspicion that my phono stage gain was not perfectly optimized for the ART-9 as I had to keep the amp volume at 9 'O clock. Now I am able to crank it up to 10 with DL103R thanks to its lower output, but I should have set phono gain at a slightly lower level with ART-9. All in all, this is the great escape!

I have managed to extract a bit more from it than I could from ART-9 by changing cartridge loading to a higher 300 Ohms.

I don't understand how you can extract a bit more using Conical stylus instead of LineContact ? It's quite opposite direction. Maybe it's personal preferences. 

The lowest possible gain for MC is always preferable until the sound is acceptable. 

You can always unload you cartridge using 1000 Ohm or higher.