I would say go for professional as I did. Platinum would be OTT!!
I weighed up what I have and Pro was the way to go.I also have what you have got and when you look at the difference In the list Pro Is the one to go for.
I do not sing and that was another factor. Me FOG HORN!!!
I was dubious about going this way and wound a few people up,but I can now see the advantages.
Pro loads up faster than X3 and touch wood ,no problems.
So far ok and I still have to put the ins file back In and a few other tweaks and adjustments.
With my Scarlett 6i6 all is running like a dream.
Also I kept X3 on the computer until Professional found all of the plugins and then uninstalled X3 once I was happy.
I say now go for it and load up everything carefully and read Instructions and you should be sailing.
I was happy at £78 and that Is usually what Sonar cost each year with X3.
Have not found any bugs yet only have a sore throat and lifeless and a nasty ulcer on the end of my tongue
"The pain oh The Pain"!!
ALL THE BEST
john