i think the disconnect problems are occuring because of the interaction between centrino and intel wireless cards, in which the power management functions decrease power output of the wirless card which would result in dropped signals.
no one makes a bluetooth combo mini-pci card, yet
you don't get centrino sticker if you get the dell. but who cares
i ran speedswitchxp on my 700m, but i wasn't getting the battery life i was expecting. when bios A02 came out i uninstalled speedswitchxp and it resulted in my 700m getting battery life to what i expected. also, i had noticed that speedswitchxp would override power management functions under the wireless properties...so there are three things working against each other: speedswitchxp, windows (the lappie), and the wireless card. now since the lappie and the wireless card are supposed to work harmoniously b/c of centrino, i think speedswitchxp was interfering. bios A01 did badly in power management of the battery, and i got better performance out of speedswitchxp, but that changed with bios A02.
at least for the i700m, i don't think it will matter which one. if there is a range difference, it is minimal and i would be hard pressed to see if anyone really can tell...with my 2200 i can get signals from the coffee shop two blocks away when it is raining.
as far as signal drops, i haven't had problems with signal drops with my 2200bg.
but if people are having signal drop problem, i would look into conflicting power management things as the biggest culprit if all else is working well.