I haven't used the Driver, but the 12V Drill exceeds my expectations. It's the most powerful 12V drill I've ever used and is now my "go to" tool for drilling holes up to 12mm in mild steel sheet. It cannot replace the 18V equivalent if you're getting into more serious holes though, such as a 38mm hole-saw in sheet metal. This is where the 18V Drill with a 6AH Forge battery really shines.
The one thing which I feel lets the 12V drill down slightly is the chuck. - It will not grip a 2mm plain-shank bit as well as the 18V drill chuck does, so the bit tends to slip further into the chuck when you need to press hard to make a pilot hole in stainless steel sheet.
Apart from that, I'm really impressed with this little 12V Drill.
The 2AH battery included in the kit might be fine for the Driver, but I feel it reduces the Drill's maximum potential a little, as when the Drill is worked hard, the battery will quit before the Drill does. If you want to use this Drill to its full potential with a compact battery, use a 2.5AH High Output battery instead.
The 4AH battery included in the kit is a pointless size for my use case as it's too bulky for this compact Drill and I simply reach for my 18V Drill when I want more power than the 2.5AH High Output 12V battery can provide.
I think this kit would be generally more useful if two or three 2.5HO batteries were included instead of the 2AH and 4AH standard duty batteries.