Internal SSDs would be the best upgrade, Large mechanical are second, Booting to FW and running everything via the FW drive is 3rd
Lacking a G4 Cube or a
standard G4 iMac here -- "testing" was done with the Iomega Mac Companion using various types of drives and OS installs before focusing on a Samsung 120GB SSD. Used a 1GHz DP Quicksilver with the SSD mounted and formatted inside, using an Addonics (
thanks billyboy, I'll send it back to you soon) SATA bridge to install OS 9.2.2 and OS 10.4.6 on two separate partitions... before then moving the SSD back into the Iomega enclosure for boot/mount tests on the Quicksilver, a 20" G4 iMac (FP) and a G4 Mac mini (with the MacOS9Lives OS 9.2.2 Mini install).
The OS 10.4.6 partition mounts and boots on all three machines via (800 to 400 cable) firewire. OS 9.2.2 is another story. 20" iMac (FP) won't boot any version of OS 9 anyway... and the mini (nor the Quicksilver) will boot the installed OS 9.2.2 either. However, the mini will even boot the OS 10.4.6 partition... via USB connection. (Go figure that one out.)
Iomega/Samsung SSD does mount and is available for file writes/transfers now (without un-plug / re-plug ritual). As for being an external boot drive in other than "emergency" recovery situations... DH's insight concerning the internal SSD installation being optimum, is dead-on. This is a very flexible little enclosure but as far as being an external boot drive to possibly increase overall performance... not so much.
As I recommended this enclosure to you... if you'd prefer to try your first choice instead, I'll buy this one from you if you wish and you can then try the other one. PM me. This one's going back upstairs to be shared between the newer iMac and the Mac mini.