I just bought widgetlocker a couple days ago. It is very fluid and responsive, and very customizable. You can make it look like stock D1, or add widgets. I use the music widget since you lose the stock lock screen music controls.
It also has other sliders like rotary D1, htc, and iphone.
The far right pic in my sig is an example of how minimalist you can make widgetlocker. It's really smooth, as stated, but the best part is that you can turn the damn unlock haptic feedback off.
I tried widgetlocker, but my corp security policies require a PIN to unlock. When widgetlocker would come up, I'd dismiss it, but then the normal lock screen would show up, which I'd have to dismiss and then enter my PIN. Is there a way to make widgetlocker work nice with a PIN?