After Build 23081, the next one that‘s looked upon is Build 23502 experienced by htcpedia. Have a glimpse at the changes in Windows Mobile 6.5 Build 23502 (COM5):

• Faster, stable and more responsive than any of the previously leaked COM3 and COM4 Builds.
• Bottom taskbar color is changed to Vista-like dark blue.
• Some GUI fixes for Volume Control.
• Graphically enhanced Scrollbars and checkboxes.
• Graphically enhanced buttons throughout the operating system.
• New and improved Contacts app which was first seen in Build 23412 (COM3 Branch).
• Kinetic flow (ala iPhone) at the start and end of any list view like in Contacts and File Explorer has been removed which is kind of a step down in my honest opinion

[...]

The ASUS P565 is a windows mobile device that is using the fastest processor for mobile phones. ASUS even advertises it as the world's fastest PDA-phone. Well, it should be fastest Windows Mobile phone and not the fastest PDA-phone. With a 800MHz processor in it's heart, the ASUS P565 surely promises great speed. Read the full review! [...]

Now, it is possible to skin the volume control of the SE XPERIA X1 easily.

INSTRUCTIONS
1- Uninstall any other HTC VolumeControl app first
2- Install SDKCERTS
3- Copy the CAB to your phone and click it to install
4- Restart phone immediately

[Download from here]