I think Ms. IsleOfMan COULD get used to the trackball, but has been known to give herself time to acclimate and quickly abandon devices with interfaces different than she is used to. Also, buying a 8100/8300/8800 without signing a contract (something she's not in a position to do anyway) would be prohibitively expensive.
There are refurbished 8100s available from AT&T for $50 w/ 2yr, but again, she can't do an new contract right now. Are their any refurb 8100s anywhere else on the market?