You can use IPB for V4 and other models like the G2 girls, just click on 'Create New' and follow the prompts. If you want to try the file I made for V4 you can get it  here http://www.jenti.co.uk/supplies/Victoria%204.ill
put it in the 'Injection Pose Builder/libs' folder. I have never found V4 any slower than V3/A3 etc.