Also Lenovo haven't been owned by IBM for quite some time. I'm sure some of their product lines still show high quality IBM heritage but it cannot be assumed.
There's no product line for servers, lenovo bought the desktop and laptop business, IBM still make their own servers...
The ThinkServer family is the result of an agreement with IBM where Lenovo will produce single and dual socket servers based on IBM's xSeries technology. Lenovo was very keen to point out to us that this agreement is not an OEM deal but that it is actually manufacturing the servers itself in China.