You say you're having trouble with clean contact (fat and thin). Why not take a lesson or two and solve this problem before you buy new irons? After getting the contact problem resolved, you might consider an iron fitting. You don't know how irons will fly until you get a fitting. I worry you don't seem to be considering proper shaft for future irons.
As for your irons list... Technically, the X20 irons (circa 2008) are SGI clubs. But, the irons had a Uniflex shaft (between R and S in flex). and don't balloon the short irons like you might get with G10 or Big Bertha irons fitted with stock shafts.
The X20 descendents, the RazrX and XHot irons, are classified as GI clubs. Stock shafts: RazrX irons had Uniflex shafts, while the XHots have either graphite or lighter-weight Step 85 steel shafts.
Also consider the RazrX-NG irons: Starting with the X18R (reissue), Callaway normally offers a variation on the previous marketing cycle's mainline iron to appeal to the $399 price point. This year, the RazrX-NG (new grooves) irons fit this slot.
Note: If you're a 15 HDCP, you should list that under your avatar box, not 1.3 HDCP.