I tried the update but went back to the non-beta version. With this new beta, the interface would hang for fifteen seconds or so after each thing I did when I had a large scene loaded.

Stonemason's Streets of the Mediterranean, V4, clothes, motorbike, millennium cat.

Vue never went above 1.4GB RAM usage, Windows task manager showed about 4GB free so memory wasn't the bottleneck. Windows XP Pro 64bit, Intel Q6600, 8GB RAM total.

The official version of Vue runs smooth as butter.