I've owned two 4033's and put them through the paces as my go to on vocals and O.H.'s on lots and lots of albums and demos. I just recently started branching out and looking for mic's to compare to my 4033's and bought a Bluebird
then a Baby Bottle. For me the Bluebird
is better then the 4033's and have entirely replaced them for vocals and everything else I've AB'd them with. It's mainly the high's that are just a tad harsh on the 4033's that really stands out when heard next to the Bluebird. I don't know how they compare to the 4040
The Baby Bottle was less desirable then the Bluebird in every comparison I made except for acoustic guitars and so it didn't take long for me to sell that one. To my ears the Baby Bottle sounded less focused and had less high end that, after compensating for with eq, still didn't sounds as good as the Bluebird.
I really like the Bluebird and haven't had any problems with it, although it doesn't surprise me that it would be more fragile then the AT stuff. My 4033's have taken a serious beating over the past 13 years I've had them and have never failed me or given me any problems.