You could always bin the idea of upgrading your Amiga and buy mine - it's for sale on Ebay at the moment
It's extremely high spec - probably as high spec as classic Amigas come. It has the mediatorSX busboard, a Voodoo3 3000 graphics card, a Terratec512i sound card, 10/100 ethernet, 5x USB2.0 slots, a top of the range BPPC accelerator (68060@64Mhz, 603e@256Mhz, on board SCSI) 256MB RAM, 120GB HD, CDRW and it's all housed in a lovely Mirage1200 tower. It also has a fully loaded OS3.9 install running on it.
Go here for a look:
http://cgi.ebay.co.uk/ws/eBayISAPI.dll?ViewItem&rd=1&item=8175600043&ssPageName=STRK:MESE:IT
