Assistantship acceptance decision extensions?

[waterbaby]

Hey all! I've just been informed that I received an assistantship at University A that I'm really excited about. It covers a fair portion of tuition and has me doing some really unique work. It's a great opportunity, but I'm still in the running for a similar assistantship/ scholarship at University B. Unfortunately, University B has stated that their decisions are slated to be released late April/ early May, and University A is asking for a decision by the end of this week (April 5th). Though I'm excited, I'm obviously extremely reluctant to commit to anything before I have all the information in my hands! Would it be inappropriate to contact University A and ask for a deadline extension? And, perhaps more importantly, has anyone had success with being granted an extension in a similar situation?

Thanks in advance!

[rising_star]

If you search on this site, you'll see that there are lots of posts where people have asked for an extension. There doesn't seem to be a pattern when it comes to success with getting an extension though. All you can do is ask and see what they say.