If you're buying it for nostalgia the late model Powerbook G4s are "nice" machines, except when they aren't. (IE, when you hit a web page that lays on the flash/javascript/html5/etc and slows the thing to a crawl. The fans will flick on, the machine will heat up to the point you can bake cookies, and you'll be sad. Trying to play h.264-encoded video at resolutions higher than SD is another sure way to do it.) I would never actually recommend one as a daily driver in today's world; speed aside it's just plain getting too hard to find modern software that runs on them, and that includes the OS itself.
(Granted there aren't many attacks out there in the wild that actually target PPC machines running Tiger or Leopard, but you will be running a system with well known and unpatched security holes in the OS and unless you're willing to completely disable Flash and Java you'll also be running with your fly unzipped on the web.)
The biggest known problem with the 15" Al G4s is the memory slot failure. So far as I know it affects all the later Als with the possible exception of the oddball and somewhat rare *very last* model, the "High Res 1.67" that used PC2-4200 DDR2 memory instead of the PC2700 DDR of the earlier models. (I'm actually pretty miffed that my practically mint 1.5Ghz unit at some point while in storage decided to quit talking to its second memory slot. The difference between one and two GB of RAM frankly doesn't matter that much if you're running software that actually works well on these machines but it's still annoying.) Early 15" models also had a problem with white spots developing on the screen over time, but I'm pretty sure that was fixed with the 1.33Ghz and later ones. (Every single one of the 1.0/1.25Ghz first-batch 15" Als my company bought back in 2004 had the issue.)
Personally I think Leopard sucks on all G4 machines so I've never upgraded my Al's from Tiger. (I rolled back the one I did try it on.) I guess some people are happy with it but so far as I'm concerned these machines are happiest back in 2005. Turn the clock even to 2008 and they start to suffer. But, hey, if you're happily using a Pismo for the same things you intend to do with the Al it's going to seem like Warp Speed by comparison. So sure, as long as you know you're buying a time capsule go for it.
(Granted there aren't many attacks out there in the wild that actually target PPC machines running Tiger or Leopard, but you will be running a system with well known and unpatched security holes in the OS and unless you're willing to completely disable Flash and Java you'll also be running with your fly unzipped on the web.)
The biggest known problem with the 15" Al G4s is the memory slot failure. So far as I know it affects all the later Als with the possible exception of the oddball and somewhat rare *very last* model, the "High Res 1.67" that used PC2-4200 DDR2 memory instead of the PC2700 DDR of the earlier models. (I'm actually pretty miffed that my practically mint 1.5Ghz unit at some point while in storage decided to quit talking to its second memory slot. The difference between one and two GB of RAM frankly doesn't matter that much if you're running software that actually works well on these machines but it's still annoying.) Early 15" models also had a problem with white spots developing on the screen over time, but I'm pretty sure that was fixed with the 1.33Ghz and later ones. (Every single one of the 1.0/1.25Ghz first-batch 15" Als my company bought back in 2004 had the issue.)
Personally I think Leopard sucks on all G4 machines so I've never upgraded my Al's from Tiger. (I rolled back the one I did try it on.) I guess some people are happy with it but so far as I'm concerned these machines are happiest back in 2005. Turn the clock even to 2008 and they start to suffer. But, hey, if you're happily using a Pismo for the same things you intend to do with the Al it's going to seem like Warp Speed by comparison. So sure, as long as you know you're buying a time capsule go for it.