It's absolutely worth it. We don't advertise the intercooler as a power adder, but more so as a device that will continue to deliver the same power pull after pull after pull. however, that said, in our own testing we saw the intercooler dropped IAT's, even after the first pull, enough so to make more power over stock. Also, the end tank and core design is much better than stock, allowing for a slight decrease in pressure loss, making spool up quicker than stock.
At any stage in the game, you'll benefit from the intercooler. It's highly recommended, especially for the newer generation TSI's coming with an even cheaper quality oem IC!