We've split our resort stay for the last two trips, and really like it. The only disadvantage we've found is not getting enough of the first resort before heading off to the second, as someone else pointed out. Our first split-stay was for 2 days each, not quite enough, but our second was 3 days each, much better.
We haven't had any problem with packing and unpacking. It's only DD and I now, my DH and 2 DS's have decided they are tired of WDW.

So we pack pretty light, just a duffle bag for each of us, plus a bag for our excess like medicine, toiletries, etc. We usually pack one bag for the first resort, another for the second resort. When we check in, we unpack our clothes for the first part of our stay, and as we use them, re-pack the dirty clothes in the empty duffle. This way, all we have to do is pack up our toiletries and head to the second resort.
We also find it much easier to get up early and grab a taxi to the second resort, it's only about $13-$14 + tip, well worth it for the convenience IMO.
Good luck, and hope you have a wonderful trip!
