First of all, I think you mean the UM-70s, not UM-705.
If that is the case, it is made by Microtech Gefell, not Neumann. They have not been the same company for over 50 years.
They are similar in features (3 patterns, pad, roll-off), but look quite a bit different. The UM70s has a very thin body, with a larger head, while the U87 is more cylindrical.
The UM-70s has it's own sound - with a fairly strong upper mid-range presence peak. It is very similar in sound to the Gefell UMT800 (they both use the same M7 capsule), without as many polar patterns and in a smaller package. I like it on Acoustic Bass, or other sources which can use a little extra high frequency articulation. Because of it's smaller footprint, it's also a little easier to squeeze into tight spaces. I rarely use it on vocals, because I'm not a fan of too much high end hype on most voices.
If you are looking for a U87 sound, I don't think the UM70s is really all that similar. On the other hand, you can probably get one a little cheaper than a U87.