Question for GSII Intl Owner with ICS?

I've had a Samsung Captivate for almost a year and half. It's an good phone. I'm running an ICS rom on it and I'm okay with it, but the battery life sucks, and it would be nice to have faster components. So for that reason, I thinking of getting a GSII (Intl) after the S3 announced. I have a feeling the price would drop down, hopefully around the 300 range. Since my contract ends in january, I don't want to spend too much right now (I'm pretty sure the S3 is going to be 700-800 dollars).

But before I do that, I have a few questions:

1. What sort of Battery life do you get with ICS?

2. Do you have any performance slowdowns (and how)?

3. How is your GPS performance?

Also indicate if you're using the official Samsung update or an ICS Rom (and which one)

Added May 4th:

I have another question....For those of you with an ICS Rom, how does long pressing the physical home button to get to Multitasking feel? Especially in comparison to the dedicated capacitive button on the One Series or the software buttons on the Nexus.