Should I replace Denon DL-103R with Dynavector DRT-XV1 mounted

A 10x more expensive cartridge won`t give you 10x better sound, but I don`t doubt for a second that you will hear an improvement. Your SME IV arm should easily take the upgrade, it is a very good arm IMO.
I have several DL 103s and they are very good cartridges for their price. Never heard the Dynavector, though.

I went from a 110 and  103r. The 110 was better because I had to use a Denon step up on the 103r (I still have it). The 110 was better. I just got an Ortofon Black MM. It just whips the pants off my 110. 567.00. It was close to the same price as the 103r 90.00 dollars more, not 10 times. BUT quite a sonic improvement.. An MM Cart..

Denon are good carts, a GREAT re tip goes a long ways though..

I'm looking at Soundsmith Carmen MKII 999.00. 2 X not 10 X.

I bet you get the biggest bang from the two I mentioned. From there on up it is a fine line of great EARS, and great acoustics. From that point it is the 50k TT with 10K tonearms and 10K carts. (bragging rights so to speak). 

If the room is right and OK gear.. LOL with my ears. I'll be REAL happy.. I haven't even got my phono stage yet. The C20 Mac with the hot rodded MM , MI and MC phono section is just killer.. Carts and phono stage is real place the union really starts. Just like that Denon SUT, I have. Some swear by them.. Yet a little work on a valve phono stage ran circles around it.. The C20 with Samra's touch..

The MATCH is the key... 

Regards

Someday I will replace a Denon dl103R as well so interested to know some good options.

Linn Axis with Linn Basik tonearm, Electrocompaniet step up transformer (with home grown mu metal shielding for no noise), Audio Research sp16 phono stage.

Dead quiet and sounds great to my ears.

esputnix, Tell us about the rest of your system, and you will get better advice.  The SME IV is a good start. A lot of audiophiles believe that a mediocre cartridge on a good tonearm and with good downstream equipment is a better way to go than a top end cartridge (like the Dynavector you are considering) on a mediocre to poor system. I am in that camp.

I have heard both. The drt xv1 is WAY better. What I am not so sure about is if the excellent SME IV is a particularly good match for either. Hmm...