Well Im confused about something......the Steyr and FN are kinda the same shape/style poly doa carry kinda thing......the CZ40 is an alloy framed, 1911 gripped fullsize CZ....the opposite of the others in everything but caliber.
If youve been cruising the gun auctions...I know why youre confused...alot of people call the CZ100 a CZ40! Not the same gun. The CZ100 IS LIKE the others. Poly/doa bla bla bla.
Now for personal opinions....
The FN is a class act. Designed by the guy who did the Sigma for S&W years ago....looks the same..but not even close in internals.
FN is an outstanding maker of arms..the 49 has a very nice trigger once they are broken in and the rest of the gun follows suit. True second strike trigger...unlike S&W, Glock, Kahr etc...meaning everytime you pull the trigger you get the striker to fire. Hell at a store close to me they have the 40 with nights for 339$....good deal.
The Steyr is in the same league....maybe a little higher. Steyr guns were the first to offer the striker fired guns....way long ago.
They have the technology few have these days....The gun has a different sight arrangement, lower bore axis for less recoil (it works too) and is priced about the same as the FN. Another good choice.
The CZ100 (Ill bet thats what you are talking about) Great gun...ok to poor trigger. Smaller/slimmer than the rest and cheaper too. Absolutely reliable, accurate and fits my hand a little better than the others. Real second strike trigger like the FN...the Steyr I believe is like that also but its been a while since Ive shot one....hmmmmm!
The CZ 40 is a damn fine gun...but is hit and miss among CZ'ers as the grip angle is so different. I personally love it and the 2 Ive shot are bloody nice guns. Great d/a trigger, light and great sights...accurate as hell....just a nice gun ...if the grip agrees with you.
For me they are all so freaking close in quality, price and function...you wont lose either way. FN and CZ offer the best support in the country, for what thats worth.
Shoot well