I wasn't sure if you were talking about the V lenses or the H lenses from the initial post. Both have 120 and 150 focal lengths.
In the H system, the HC120/4 is quite a bit larger than the HC150/3.2 ... like most macros the 120 is optimized for close focusing and has a longer focusing throw than the standard lenses. It is quite a hand-full for hand-held work.
A nice Portrait lens set for the H is the 50, 100 and 150 which all take the same filter size so you can get a variable ND to enable faster aperture portraits in brighter shooting conditions.
50 for environmental type portraits, 100 for full length portraits, and the 150 for head and shoulder portraits.
A very interesting addition eventually may be the HTS/1.5 for "controlled focus portraits" ... it can take up to the 100/2.2, and adds a lens factor of 1.5X making it a 150mm with rotating T/S control of OOF areas.
-Marc
Note: the 210/4 is used by quite a few head shot shooters ... it also takes the same filter size as the 50, 100 and 150.