Summary: I have the 450 Series II microphone. I bought it used via Ebay for $35 with the cable but without a connector installed on it. I asked the ham community for the pin out info to wire this mic to my Kenwood TS-450SAT. It has a round 8 pin connector. I got the info quickly and had no issues in terminating the wiring. Much to my surprise, I received excellent audio reports.
Excerpt: I use this for overhead paging in an educational lab, speaking to students as they work with simulated patients. The solid construction is key, as the mic gets a lot of us and is moved around quite a bit. Audio is clear. Some may see the need to wire your own connection as a con, I saw it as a pro. Flexibility is key. A little pricey for the simple job it is doing, but I think you are paying for durability.
Summary: I recently purchased a Ten Tec Omni VI Option 2, and needed a microphone for it. Having had such great results with a Shure 444D on my Kenwood TS-830S, I went looking for another Shure microphone. I snagged a 450 series II off ebay for ten bucks and change. It turned out to be new, but not in a box. I have nothing but good things to say about it. This mic has a lot of gain. I have the mic gain pot at 9:00 which is barely on.
Summary: I have an older version of the model 450 mic. Mine says "Made in Evanston, ILL, U.S.A." on the bottom sticker. This was new, unused in the box when I got it new from a retailer, then it sat around for many years before finally wiring it to a Kenwood TS-440S transceiver. First off, the Shure model 450 has a LOT more gain than the stock mic, and I have to run the mic gain on the radio about half way. On SSB, the 450 sounds simply amazing.
Summary: Update, I have been watching these on ebay, everyone searches for the 444 mic and the prices reflect that. This mic is essentially equivalent except with the impedance option. I just got a NOS US made one, in the box, for 35$ and no one else even bid on it. I might have easily payed double for a NOS 444 I think, or more. And they look the same, the difference is on the bottom.
Summary: Wonderful dynamic element, very good audio. This microphone does not have preamp, if you want to adapt, here is the complete project: http://www.biagiobarberino.it/shure450.htm Eccellente capsula dinamica, ottimo audio.
Summary: Probably can say everything about this that you can say about a 444. Slightly different curves but the 3 kay-cee response bump is there in this one, too. Actually a huge bump up at that freq. Good for SSB. You can select impedance on the bottom, so unlike the hi Z 444 you can run this into a newer rig designed for low/med impedance dynamic mics and get the 444 sound, more or less. Made in Mexico. But probably all of Shures stuff is now made in Mexico.