Trash80toHP_Mini,
Your questions are too general.
What toys are you talking about? IIxx family? SE? Quadras? NuBus PowerMacs? PCI PowerMacs? Internal or external? Bootable? The only drive in chain or one of several? What OS? What formatter?
Each case have to be examined separately, I'm affraid. The newer your Mac is, the less problems you'll encounter.
From my own experience, spanning from Q650 to PM9600.
1. Seagate's are best. Quantum and IBM less so.
2. Drives with custom firmware could be problematic.
3. FWB software is mandatory. ATTO Express ProTools is very good addition.
4. On NuBus - Jackhammer is best. ATTO SEIV not so.
5. On PCI - Adaptec 2940UW is best, ATTO acceptable. (Tip: use cheap 2940UW's from PC's, resolder EEPROM and reflash them with Mac firmware, when needed)
6. On 68k Macs - watch 2GB boot drive limit.
7. External DataExpress DE100i-SWCU2 hot-swap enclosures are very good, i use them when I need to mount SCA drive quickly (just 4 screws) Note - these need to be equipped with isolator board to be really hot-swappable on a Mac, but work fine otherwise - i.e. you have to reboot.
8. SCA to UW adapters were discussed previously
