As you can see by the image, the brushes seem to not load textures properly or at all in most cases. Only started happening on 13.2 drivers beta 6. However the performance in all source games have improved, but only TF2 gets the texture issues.

Processor Information:
    Vendor:  AuthenticAMD
    Speed: 1500 Mhz
    4 logical processors
    4 physical processors
    HyperThreading:  Unsupported
    FCMOV:  Supported
    SSE2:  Supported
    SSE3:  Supported
    SSSE3:  Unsupported
    SSE4a:  Supported
    SSE41:  Unsupported
    SSE42:  Unsupported

Network Information:
    Network Speed:  

Operating System Version:
    Ubuntu 12.10 (64 bit)
    Kernel Name:  Linux
    Kernel Version:  3.5.0-25-generic
    X Server Vendor:  The X.Org Foundation
    X Server Release:  11300000
    X Window Manager:  Metacity
    Steam Runtime Version:  steam-runtime-release-i386_2013-03-08

Video Card:
    Driver:  ATI Technologies Inc. AMD Radeon HD 6520G
    Driver Version:  4.2.12172 Compatibility Profile Context 12.10.17
    Desktop Color Depth: 24 bits per pixel
    Monitor Refresh Rate: 59 Hz
    VendorID:  0x1002
    DeviceID:  0x9647
    Number of Monitors:  1
    Number of Logical Video Cards:  1
    Primary Display Resolution:  1366 x 768
    Desktop Resolution: 1366 x 768
    Primary Display Size: 13.54" x 7.64"  (15.51" diag)
                                            34.4cm x 19.4cm  (39.4cm diag)
    Primary VRAM Not Detected

Sound card:
    Audio device: ATI R6xx HDMI

Memory:
    RAM:  3427 Mb

Miscellaneous:
    UI Language:  English
    LANG:  en_GB.UTF-8
    Microphone:  Not set
    Total Hard Disk Space Available:  187739 Mb
    Largest Free Hard Disk Block:  61155 Mb