Job Promotion? Or Take Advantage of SID?

OK, here's the delema and a little history to start off with:
I work for a Telephony Company that specializes in Pre Paid Cellular systems, we have accounts all over the planet (none in US yet). I've been working here for 3 years in July, my job is basically I do alot of shit! I review, validate, and approved installation documentation, install and manage our test lab, produce software on media's (dat/cd's) our software and unixware, oracle etc. I work for the product support group and basically work my ass of for them, and the rest of the company at the same time. I came with hopes of being a PS engineer, well I'm making OK? money right now and I'm working UNREAL f'n hours with no OT compensation(salary sUX!) Wednesday, I get told that they want me to start doing PS training and working in the PS and learning all the systems/software/troubleshoot etc., PS works unreal hours! and when on call (1 week at a time) you can work an easy 100+ hours in a week. I mean already I aver 63 hours a week! It's a great opportunity for me and furthering my career, but ....
>>>ALL THE ENGINEERS MAKE AN AVERAGE OF 64K OR SO A YEAR, THERE IS NO GUARANTEE THAT I WILL GET THIS MONEY EVEN THOUGH I'LL BE DOING ALL THE WORK (I DO ANYWAYS) THAT THEY WILL. WHAT THE F"K SHOULD I DO? TELL THEM NO PAY NO PLAY? TAKE THIS JOB A SUCKIT! I'LL KEEP DOING WHAT I'M DOING?
Any advice? Thanks!