I have 1911 with both but generally prefer a Flat MSH.

Some say Mr Browning got it right with the flat MSH the 1st time.
The 1911A1 got the arched MSH over the 1911. This was to correct the tendency to shoot low when pointed and fired (point shooting). It (the arched MSH) in fact did just the opposite when the gun was raised to eye level and aimed with original sights.

On all of my 1911's I have an arched MSH and a short trigger. This combo fits me the best.

The Army went to the arched mainspring housing in 1917 I think it was because they pointed more naturally with them. Seems like all of the commercial ones followed suit until sometime in the 80's and now the trend is back to flat ones.

I prefer the arched mainspring housing over the flat......But have both and shoot both fine.

I would think that given my Glock tendencies I might prefer the less upright backstrap with the arched mainspring housing. However all I've ever had with my 1911s are flat/flush MSHs (though one is in a fastback configuration). Seems that all I ever notice is that they feel skinny and uncomfortably un2x4-like any way one scores it.

I also prefer arched, very few if any modern handguns have a flat backstrap.

Many years ago, one of the first and few things I changed on my Colt Combat Commander, was the arched MSH. The other was the short trigger. The flat MSH and long trigger work a lot better for me but as someone else said, it's just a matter of preference.

Flat housing with a long trigger is my preference.

I greatly prefer an arched MSH with a long trigger.

As many have said, it's all personal preference.

I prefer an arched MSH. The pistol naturally points low with a flat housing.

quote:

Originally posted by Texas Bob C.:
I prefer an arched MSH. The pistol naturally points low with a flat housing.

This

Arched and short triggers. How I have my 1911’s set up

Another fan of the arched housing, I just shoot better with it.

I much prefer the flat MSH and long triggers for my 1911's. The arched MSH causes me to point high. With the flat MSH, I seem to be naturally on target. I think that I could get used to an arched MSH, but why bother when the flat works so well. In the end, it is personal preference.