Apparently the Siemens direct-drives are even lighter: the page for the SWT-6.0-120 says THM is "under 350 tonnes". (With that, it presumably beats the Vestas V164-8.0 MW in power/THM.) Do you have a similar number for the SWT-6.0-154?

Also, looking at the rotor diameters, any chance the Alstom Haliade 150-6MW and the Siemens SWT-6.0-154 will be up-rated?

_{*Lunatic*, n.
One whose delusions are out of fashion.}