I have used optionshouse for quite a while, they still offer the 0.15/contract. I would call them a no frills account and you can save a lot in fees if you don't need a lot of personalized trading help. I use them for most of my trading but use schwab for trading analysis, research, etc. I am happy with optionshouse.
I haven't done it myself, but in my positions when I click on, say, the Sep33 calls, it brings up "Exercise AGNC Options".
Also, their online help (for account holders, at least) says this:
How do I early-exercise an option?
If you wish to early-exercise an option contract prior to expiration, you must place the exercise request directly into your OptionsHouse account by 3:15 PM CT. You can also call the OptionsHouse Trade Desk at 877-653-2500 ext. 1 and submit your request by 3:20 PM CT. Failure to do so will result in the contracts not being exercised.
Thanks. Direct word here is worth tenfold of what I read on that review list.
One consistent complaint on that list I read was fill time even when bids above offer were entered. oh and long lag time for deposits to show up in the account, even electronic tranfers took four days. Four days is a deal killer when opportunity knocks.