By one metric anyway. Click through for a graph showing the correlation between spending and wins over the past decade. The Cards are above the line, meaning that they've gotten better-than-average value for money.
There is a clear correlation between spending and wins, but there also appears to be a threshold: if the Cards can continue to spend in the $95-100mn/year range, they put themselves in a good position to average about 90 wins a year. In a division of weak spenders that will often be enough for the playoffs.