We gave up way too much for Garza. He is an above-average pitcher at best. The only good thing is he should be entering his prime, which will hopefully translate into better numbers and consistency. But to give up that much young talent is ridiculous. If history tells us anything, Garza will probably give us 2-3 very good(not great) years which will then allow him to land some over-priced, super long contract that we will be stuck with as he declines after his prime.
I'm a little more optimistic. The Cubs bullpen spent way too much time on the field last year. They needed a guy who could eat up innings. Garza pitched over 200 innings last year with 3 complete games and posted an ERA under 4 in the best hitting division in baseball. Not to mention an ALCS MVP award. I think it's fair to say he is at least above average. He could turn into a legit #1 in the NL. Time will tell if this is a good deal or not based on his performance and how well the prospects do in Tampa.