just to add a bit more to this thread, if we're talking specific functionality i would say go with what you need...for my first pda the m100 was fantastic, but being the geeky sort i wanted something more powerful not long after...and two years later finally got me a zire 71. point? if you just want an electronic extension of your address book/ical, etc then go with something on the lower end; sony's sj22 is color and has memory stick expansion, and you can get it for ~100.00.
if you are looking for something more advanced but not cutting edge, the sj33 is really nice; it has the same feature set as the sj22, plus an mp3 player.
however, for ~50.00-100.00 more than the sj33 (which is @200-250 right now) you can get the Palm Zire 71, the lowest-priced Palm OS 5 device, plus it has a funky built in digicam, similar to the kind on cell phones.
but if you really want to splurge, theres some wicked advanced sonys to consider...they are literally everytihng you'd need (or not even realize you'd need/want) but they aer bulky...as for high-end palm-branded devices, they are nice but only the tungsten c is really worth the price, and even then only if you desparately need built-in wifi.
--carly