I recently picked up my first Titanium, a second generation version with a 550MHz G4. Right away I started comparing it to a PowerBook Pismo with a 550MHz G4 upgrade. I was thinking that the Titanium would also have a 7410 CPU, but it turns out to have a 7450 without cache so it's probably the slowest Titanium model. Overall, the Pismo is noticeably quicker and subjectively more responsive. The other specs are also similar between the two, with SSDs, 1GB of PC100 RAM and 16MB of VRAM. The Titanium is a bit thinner and more stylish but the Pismo is still my pick between the two. I didn't own either of these back in the day, but I can see why Pismo owners would opt for upgrades over replacement. I'm sure the last iteration of the Titanium would be better, but I'm not too impressed so far.