I recently installed 12.04 through the WUBI on a Lenovo u310. The installation went fine, but when I rebooted into Windows 7, and then rebooted into Ubuntu, it immediately went to a command line 'grub' prompt.
I was able to reboot from there successfully into 12.04 (once) but then on another occasion could do nothing to reboot into Ubuntu, so had to reinstall.
The reason I used the WUBI route was that there are troubles in 12.04 recognizing the hard drives on Lenovo u310 on direct install from memory stick. This has been a bit frustrating, and I was surprised by the difficulties on the Lenovo u310.