So by "integrated FMS" you mean a multi-sensor navigational unit? Personally, that doesn't meet "my" definition, simply because I've never had one, but have used several FMSs. Also, there are PLENTY of Pro Line 21 installations in the field without INS. Does that make them any less of an FMS?
Anyhow, semantics aside, your point is well taken; my point is that the G3000 suite will be just as powerful as the Pro Line 21 (probably more so), but for sure, it may not have INS capability. Given the success of the G1000 series, and Garmin's customer service I can say without hesitation that it would be a welcome addition to most any cockpit (with few exceptions), especially when cost is considered. It's only a Part 23 installation for now, but I wouldn't be shocked to see it in Part 25 aircraft before too long.