[Quill]

This is based solely on playing with the phone in the store for about 10 minutes today.
What I saw, however, I loved. It was tough not to buy the phone today.
I love my 4900. I want a flip phone, preferably a Sanyo. I don't want a camera. This is perfect.
I compared the internal display to my 4900 display. It's bigger, brighter, dare I say beautiful.
The phone itself is taller than my 4900 when open, but very lightweight and comfortable in my hand. The anntenae is about half the size of the one on my 4900.
It is smaller and fit more comfortably in my jeans pocket than the 8100, which is the other model I have considered upgrading to.
The menus on the 5400 are much much better. Each major menu is an icon on a single screen, then you scroll through submenus after that.
The polyphonic ringers are awesome. ReadyLink was quite nifty too, loud and clear in the demo I got in the store.
I am also well chuffed by the fact it has a speaker phone, one of the features I use often on my 4900 as I spend quite a bit of time in my car.
I can't report on call quality. I'm hoping it's as good as my 4900.
I miss having a flip phone, but I think one could fill that void nicely. I wouldn't even consider shelling out $229 for the 8100, which seems bulkier to me due to the camera feature. I would, however, give serious thought to just handing over the $299 for the 5400 and not wait until the time comes to renew my contract in a few months. I don't know if I can wait that long.
What a sweet phone.