This is not a matter of personal preference, and the revisions to "Messiah" do not include using the "POWERHOUSE CHURCH CHOIR."
Handel wrote for his time, NOT with an "oh, just use what you have" caveat. The MASSED CHORUS for "Messiah" was a creation of the Mormon Tabernacle Choir. If they wish to perform works in a manner that I as a former pianist believe are not true to the composer, it is, at least for the moment, a "Free Country." After all, the TEXT, not the LIBRETTO is holy writ, so to speak.
I understand the desire of some people to view the composer's score as a "suggestion" other than instructions on how to perform their work, but I on the other hand believe that marks such as "allegro non tropo" mean "sprightly but not too sprightly," NOT "droop down to dead slow."
You may listen to the Mormon Tabernacle version all you wish: it is your right. I believe it's WRONG, but you have that right. Try listening to this:
http://www.amazon.com/Handel-Messiah-Watkinson-Elliott-Hogwood/dp/B000004CXUThis is considered the DEFINITIVE performance of the SEMINAL Libretto of "MESSIAH." I think you will agree, especially the tenor Recitative: "Comfort Ye My People/Every Valley Shall Be Exalted" and the first Chorus: "And The Glory Of The Lord." Emma Kirkby's rendition of "But who may abide" which is usually (and wrongly) performed by a bass is nothing less than angelic, and the performance of the Choir of Christ Church Oxford (treble and alto boys) is truly the voice of the angelic choir envisioned by Handel.