I posed approximately the same question earlier this year. I said I would go as far as changing out the ejector, extractor and spring loaded bearing in 9mm for the 27. I got more posts telling me to just go with a 26 and not trust my life on a conversion. Many said that it would be great for the range but just go OEM for defense.
I took that advice and dropped the 27 and now own two 26s. With a mixture of Corbon 115 +p and Speer Gold Dot 124 +p I believe I'm covered.