Actually, I don't think the price difference is that big compared to the Souchaku Henshin series. SIC's often come in two-packes, so even if you need to put 4,750 Yen on the table, that still means you only pay some 2,350 Yen a piece, which is close to the price of the Souchaku Henshins.
The thing were there really is a difference is the speed at which figures come out and they keep up with current series. In that regard SIC lets us down a bit but on the other hand, they're highly detailed and posable.
Well, that's just my opinion ...