Only my opinion, but 'tis best to buck up & save to purchase the real thing. 1675 is so damn perfect that only by owning the real thing can one do it justice. Plus it's really heating up on the collector's market (which I have been saying for a long time). You will always have to deal with the improper BPH, too, unless you slap in a 1575 (which is getting ridiculously expensive nowadays).
Now if there are accessible 1655 OEM parts, that's a different story. Again, just my opinion.
PS. I LOVE my 1675!