I'm using x2 and wondering if I should upgrade to Platinum. 
I've spent quite a bit of time finding good soundfonts in x2 and
would like to know if I can use the same ones in Platinum? 
Also, wondering if Platinum is more compatible with Windows 10? 
Thanks, 
Marsi

Cakewalk developers have a very close working relationship with Microsoft so it's a safe bet that Sonar will always be developed for the most advanced OS ie Win10.

On the other hand Sonar is backwards compatible with all supported OS. Which means back to Win 7. The 2017/07 release due at months end will see the end of support for MS Vista operating System. Again that fits with Microsoft no longer supporting Vista.

There have been significant advancements in audio on Win 10 and some of these have made their way into Sonar. Hope that answers your question.

Sound fonts is a very old technology and the ability to recreate realistic instrument sounds has come a long way, but while ever you have a sound font player you should find Sonar able to play them.

Thanks, 
What about soft synths? 
Will the ones I've chosen for X2 work in Platinum? 
 
Appreciate the info, 
 
Marsi

As a rule, yes. The problems people usually have with older plug-ins are usually related to the OS. Either the old synths require elevated security (IOW running SONAR as administrator) or are stuck at 32bit. Plug-ins stuck at 32bit often do work in 64bit SONAR but there is a performance penalty and typically are not maintained by the manufacturer. SONAR still ships as a 32bit DAW too. This may be a solution for old plug-ins especially DX plug-ins that have no convenient way to run in 64bit DAWs, Plug-ins that have not been maintained in years should be retired. Updating everything but a few plug-ins is not a recipe for success.
 
If you have any doubts, load the demo and test them for yourself.
 
Of course, you will still have X2 to aid in the transition.

Good info 
Thanks! 
Marsi

I think that the sfz format is probably the new soundfont.  Grab the free Plogue sforzando player (VST instrument) and standalone app.  https://www.plogue.com/products/sforzando/
 
There are some free sfz libraries available, as well as the sfz files from Dimension Pro will open in it.
 
As a bonus, an integrated format converter should get you started!
 
You can also drop SF2, DLS and acidized WAV files directly on the interface, and they will automatically get converted to SFZ 2.0, which you can then edit and tweak to your liking!
 
Out of curiousity, I just dragged a copy of 'FluidR3 GM.SF2' onto the GUI of sforzando, it easily imported the file. I can now select individual GM instruments from the menu under the "Converted" category.  I can also open the new sfz file in a text editor by pressing a button on the GUI.

As abacab says, sforzando is great for converting and playing SF2 soundfonts.  A word of warning though - there is no guarantee that they will sound exactly as they did in your previous player.  I've tried to bring a few old projects into Sonar this way and had trouble recreating the original sound.  The basic wave information is there but there is a bit more to it than that.  You can edit the sfz text file to tweak envelopes, filters etc. but you need to know what you're doing (and I don't really, so it becomes a trial and error thing for me) :)
 
AMB
 

The OP also never mentioned what plugin is being used to play soundfonts in X2.
 
At this point in time, I would expect most plugins that worked in X2 to continue to work in Platinum, with the exception of the issues described above by scook regarding the 32-bit/64-bit thing.
 
So the sfz format provides a migration path away from sf2, but is probably not a drop dead issue at this point.