Two COMPLETELY different pistols. What do you want, a stellar hi-cap, large range gun/service pistol with accuracy much better than the Sig, or a semi-compact carry pistol?
The Sig P228 is a fine all around 9MM, but it compares more to the CZ PCR or P-01 than SP-01. However, my P228 is not as accurate nor as easy to carry as my PCR. It is slightly larger, blocky, with an annoyingly high bore axis. My CZ's run rings around it at the range, are equally as reliable, more accurate and easier with follow up shots.
If you want that type of gun, maybe a trade for a PCR is in order? Whomever is getting your SP-01 is getting a great deal.