Z4 E30 vs. M3: Which is the Better Buy?

As we consider purchasing a BMW, I'm torn between two of my favorite models - the E30 Z4 and M3. While both offer impressive performance, they cater to different driving styles. The Z4 is a more comfortable grand tourer with a relaxed demeanor, whereas the M3 is an aggressive beast that demands engagement from its driver. Which one would you choose?