Gmail vs Android Mail vs K-9

So I've used Mail and K-9 to manage five different emails, but mail doesn't let me switch between identities like K-9 does, and K-9 is a bit more powerful than I want.  So I'm testing the gmail app.

So question: in my personal gmail (web version), I have a company email account forwarding to the personal gmail because I don't like that company's web software.  Now, my personal gmail account is synced to my phone, and of course emails from both accounts make it to my phone.  When I get an email from my company email, it of course forwards to gmail and syncs into my phone.  Now, the email I get on my phone displays the company email as the "sent to" address.  When I hit reply, though, it's replying using the gmail address.

Any thoughts I can make it go through the company email?  Or do I need to clarify better?  =P

Huh... well, that's a bummer.  The company one doesn't use MS Exchange.  How can Verizon charge for the use of something another company charges for?  Is that considered double dipping?

Well, I have three gmail accounts set up on the gmail app, a yahoo account set up on a downloaded yahoo app, and that company's email set up through imap.

I have too many emails...  =P

Have you heard whether or not Google will set up their gmail app to allow custom "from" addresses?

Google is not letting the GMail client to access private servers.

My accounts use GMail and are private addresses because we left the in-house mail servers for both companies and moved everything to Google Apps. It is cheaper for us than keeping the Exchange server and the Lotus Notes server.

I think Google is pushing now for this kind of solution, and not for letting their GMail client to connect to other kinds of servers, or to allow custom "from" fields.