Out of these two cartridges which would you choose?

I would go with the Ortofon 2m Black

sbank.....Mine didn’t cost anywhere near that price...(I think I paid 2....) If that’s too much go for a black.. The upgrade is significant with either of my suggestions. The Expressimo weight is a significant upgrade as is the wiring.  I've heard both of the Ortofons in an RP8 with nothing to find wanting ....every cartridge must be set up properly with enough gain et al in the head amp.

I have the 2m Black for over 3 years and I'm always regretting the turn to MMs after I've sold my VDH Colibri XPP
From the current available catalog of new MMs, the 2m Black is top after the Clearaudio Maestro II and perhaps the AT-150 MLX in a few set-ups.

The 2m Black is not near a revelation upon the 2m Bronze.
The characters are the same. So, if you like to really change something, choose the best without the need for future upgrade :

http://www.ebay.com/itm/Headshell-JVC-Tonabnehmer-Neu-NadelJVC-Z-1S-Komponente-fur-Plattenspieler-/2...

and then set an order for :

http://www.jico-stylus.com/advanced_search_result.php?search_in_description=1&keywords=DT-Z1S+ne...

I agree with your priorities about saving for speakers, 
although it would be nice to tell us what is your poison 
some thoughts & opinions from experienced members can be helpful. 

And please do not forget that until the time of this distant future upgrade, there are 2 major things that matters and really worth to consider :
 Power Cables & Speaker Cables from Physic Harmonic 
http://cablesilk.simplesite.com

Best to you

I have both carts and can tell you I prefer the 2M Black. The 20x2 is very balanced and detailed but the 2M Black is more dynamic and involving as well as detailed. I also have the 2M Bronze and like it better than the Dynavector.

I have both carts too. That is a hard choice indeed. I cannot sway you to one or the other.

I would, however, say if listen to more acoustic music, folk, blues, and smaller jazz groups I'd go with the Dynavector 20XH.  The Ortofon 2M Black is fantastic though.  It's really great just giving you a macro view--a comprehensive picture.  It can really rock.  The 2M's weakenss, if any at the price point, would be micro details; it does not unearth as much detail as the Dynavector--at least in my system.  All of that said, you cannot go wrong with either cart.  

Both of these cartridges did something similar for me--they opened my eyes to how vinyl can really best digital.  They made me more curious about other cartridges more than any other piece of gear has--save for me moving up to a really decent phono preamp.