I'll answer both questions if thats okay.
The prop ester is very short lived, it requires daily or every other day injections. Cyp is a much longer ester, not too de-similar from enanthate, injections every 3 days whilst on will provide stable blood levels though of course the ester is in the system much longer.
What IFBB is saying is that using a daily injection of test prop, 50mg perhaps brings your total count of steroid up, will kick in faster etc.
Since i was away from this place for a while, it seems to have become the thing to be reccomending short cycle, 7-8 weeks. Whilst there are some benefits to doing this, recovery primarily, i am still a firm believer in 10-12 week cycles, i have tried both and the longer cycle wins out for me everytime. So yes, shoot for a 10-12 weeks cycle with your cyp at 500-750mg per week.