Congratulations on your brand new Casio WK-7500 Linda! Looking forward to hearing your indepth review as well by the way. $500 bucks is peanuts for this very competent arranger in my opinion. I would say it's practically on par with the Big Three "mid-range" offerings that cost 3x as much too if you ask me.
Kudos to Casio for improving their arranger workstation line with what seems to be every new model they produce. Here is a demo of the Organ capability on the WK-7500:
Casio WK-7500 Organ(s). The Organ sounds alone are worth the price of admission if you ask me. It's a great little keyboard to practice your skills on too needless to say. And it would make a suitable back-up 'in a pinch' as well too no doubt. Although, I'm still waiting for Casio to enter the "high-end" market at some point in the future that will better suit my needs. If Casio ever masters high-end arranger features/functions/sounds and significantly beats the competition pricewise - look out!
There could potentially be a mass exodus away from the Big Three as people by the boat load jump ship and head on over to Casio. Think of it? A company producing astoundingly proficient high-end keyboards at a "fraction" of the cost of Yammie, Korg, Ketron, and/or Roland if Roland ever decides to make another totl arranger again.
For example, Casio producing a breathtakingly competent high-end arranger for... get this... $1,500 including tax (VAT)!! I'm talking everything included - including the kitchen sink.
Yammie, Korg, Roland and Ketron are probably shaking in their boots at the thought of such a dire prospect to their own bottom line(s) I would imagine too.
They would finally have to significantly cut their currently outrageously astronomically high prices that they currently "bilk" their customers out of to finally fall more in line to what their products are actually worth and people could more easily afford - which currently MOST can't.
All the best,
Mike