I’m not the expert that others are, but here's my quick answers.
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If you use 1Password, as I understand it, a new, complex password will be created in place of the ones I'm currently using. So if I am on somebody else's computer, how would I know how to log in?
1Password will NOT override any of your current passwords automatically. I’ve never had it even ask me if I wished to do so. If I, on my own, ask 1Password to create a new password for a site, then it does that and asks if I wish to update my login.
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So sites have very specific rules about passwords (just so many characters, some have to be numbers, some punctuation, etc.). How does 1Password match its' password to these rules?
There are options within 1Password for all these things. - strength
- length
- “Password recipe”
- pronounceable
- digits
- symbols
See attached graphic for a bit more info.
[attachment=3183:OnePasswordOptions.jpg]
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Would I disable Keychain in favor of 1Password? And if it is disabled, it seems that it will be hard for me to remember my dozens of existing logins.
It’s been ages since I did this (and I've not disabled Keychain - but would to know how to do so), but I’m pretty sure there instructions at agilebits on how to export the Keychain and then import it all into 1Password.
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Suppose I am away from home & create a 1Password login for a site, but then my wife (back at home) goes to that same site, how would she know that the 1Password login exists?
I have 1Password use my dropbox acct to store it’s support file. This is accessible to me on my iPhone, iPad, MacBook Pro, and my iMac. If you and your wife can both access the same dropbox acct, this would work for you.
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I guess I'm also asking if those of you you use 1Password are happy with it.....
TOTALLY!
1. ...as I understand it, a new, complex password will be created in place of the ones I'm currently using.
Nope. It can be used with that sites "Change/Edit/etc." password
I'm so glad I turned to Techsurvivors. Your answers made it all click in my brain. Of course 1Password can't change existing passwords without my active participation. Don't know what I was thinking...
So, to make the best use of 1Password, I should:
1. Begin using it to generate any new passwords from now on.
2. Invest some time changing many of my existing passwords, using 1Password to generate new entries. I would use Dropbox to sync.
A couple of more questions...
Do you find logging in with 1Password easy to do on an iPhone/iPad?
How do you handle logging in when you are using somebody else's computer, or a public computer?
I have learned a couple of things today: 1. TS / Safari does not save carefully worded and exact answers when one turns on Airplane mode. 2. Never try to use an cellular device without a generous data plan because there seems to be no way to turn data usage OFF while maintaining phone service.
So... I'll attempt to answer the following questions fro this morning:QUOTE
1. Do you find logging in with 1Password easy to do on an iPhone/iPad?
2. How do you handle logging in when you are using somebody else's computer, or a public computer?
1. The login process is exactly the same on all devices. There is nothing to do except enter your carefully created (by you, of course) and extremely important to remember 1Password password. The only difficulty is the "keyboard" on the iPhone.
After that, the interface is similar but smaller on the iPhone; a list of categories (All Items, Logins, Secure Notes, Credit Cards, Identities, Software Licenses, Email accounts) and a search box. clicking any of the categories brings up an alphabetical list of the items in that category. Entering something in the search box is an exercise left to the reader! 
In iOS 8, 1PW was able to get Apple to allow it to be used in many of the 'share' options of many apps. I think that's the box with an arrow point up and out of the box. If you don't see "1Password" in the 'places' that can share data, try the "More..." button, also. If this function is setup in the app, it will 'talk' with 1PW and handle the data transfer, automagically. Your least exciting action is to copy and paste the data from 1PW as needed. 1PW will close and require you to log in again, when you leave it to open the original app in order to paste in the data. "It's a feature, not a bug!", but it can be frustrating... I just have to remind myself that iOS is not a "real" OS. 
2. If you don't have your iDevice or laptop with you (where your 1Password app is installed), you'll be "up the proverbial creek/crick". Even if you have a device with the app installed on it, you'll still need to type it in on the non-owned computer. This can be a big security risk on a public computer/network or even a friends PC; you have no convenient way to assure that there aren't data/key loggers between you and the "secure" site. You'll have to make that decision on your own, or make use of VPN. That's beyond my pay grade Just like most of the rest of the interweb!!
Sorry for the delay, you get the same excuse I got when our train had to stop behind a slower one or take a siding to allow one by: "Sit down, shut up, and keep your feet off the seats!"
Anyway, hope this helps! BTW, didn't kimmer do a great job on explaining things?
Thanks for the heads-up on 1PasswordAnywhere. I didn't know that was available.
I'm an avid 1Password user, but unlike the rest of you, I still create my own passwords...So, I try to create something memorable, though never "easy" - complex and long, but at least having some meaning to them.
If it's a password that I use on a regular basis, I think it up myself. I started doing this after I got stuck at the bank and needed my password so they could help me with my online banking. This was pre-cell phone days, so I wound up coming home, looking it up, and going back to get help. That meant a 64 mile drive to solve my problem. So now I create my own quite often.