I'd keep the 27 , drop in a 357Sig barrel and drive on. Practice with the 40/9 conversion barrel and carry it as 357Sig with Gold Dots for social work.
I sold my G27, 'way back in the 2002-2004 time frame, after finding it too large for a true hide-out gun, and that my G29 was about as easy to conceal at waist level. (The blocky, protruding rear of Glock slides is my concealability nemesis.) One of my colleagues, a UC narc at the time, already had a G27, and wanted to have a pair of them, so the deal was done. I sold the G27 when it was still almost like-new.
Over time, I started to think I would re-acquire a Baby Glock, but probably 9mm. The probability became a reality with the Gen4 G26; the Gen4 frame locks into my hand's grip much better. Another factor was that my chief authorized 9mm as a primary duty pistol cartridge, in September 2015, and I switched to G17 duty pistols, making a G26 a logical secondary pistol. If not for the magazine compatibility factor, I might have opted for a G43, or Walther PPS, instead.
Have Colt, will travel.