I am planning to update one of my websites and want to know if I should use magento

or wait for VM1.5. So I tried to install vm1.5. Unfortunatly I didn't have any luck.
I got the error "There was an error uploading this file to the server." When I use the extension manager to upload com_virtuemart_1.5_nightly.zip.
I got the following error when I ftp the files to tmp directory and install it from there:
JInstaller::install: There is already a folder called '/xxx/www/administrator/components/com_virtuemart/virtuemart.ini'. Please initially check whether:
• the Extension is already installed
• the file names in the XML file are spelled correctly
• there are no XML files listed inside the extension.xml file
• all of the files (not including XML files) are correctly listed in the extension.xml file and there are no duplicate entries
• there is an empty folder listed from a previous installation attempt
The build I tried is: VirtueMart 1.5_nightly Nightly Build (Joomla! 1.5 only) [20091120]
configuration:
Database Version: 5.0.45
Database Collation: utf8_general_ci
PHP Version: 5.2.11
Web Server: Apache/2.2.3 (Red Hat)
Web Server to PHP interface: cgi-fcgi
Joomla! Version: Joomla! 1.5.15 Stable [ Wojmamni Ama Mamni ] 05-November-2009 04:00 GMT
Installation of VM1.1.14 abd other components works perfectly. So does anyone has any idea.
P.S. I know this is not the right place to post this but I cannot add a new topin in Virtuemart 1.5
