I've watched too many people struggle with the RASA and the Hyperstars to feel comfortable with them as slam dunk recommendations. I would strongly urge anyone buying one to get with someone who uses one if possible to see the challenges. For some people, getting the tilt/collimation/focus just right is, if not easy, straighforward. For others, it will be an exercise in futility. My own recommendations would be a fast refractor or one of the Tak Epsilons. Again, any fast reflector is going to require more care and tending than a roughly equivalent fast refractor. My two observatory partners use Taks and produce wonderful data with them.
I'm pretty happy at F5.2 with my Tv127is. I recommend the Taks over it but it's a close race. My scope is no 11 years old and still in fine fettle. The build quality is excellent and you can get a reducer to take it down to F4 is you like.
I don't want to hijack the thread but I really can't see a PW 12.5 CDK working well on a CEM70EC. While the tube is shown as weighing only 46 pounds, once you add the focuser and the extra dovetail (really needed if you plan to carry the scope) you're over 50 pounds. Add in an imaging system and it's not hard to reach 60. The other big problem is that all of the weight is at the back of the system. That gives the mount a real workout because of the 31" moment arm. I can provide a lot more discussion in a different thread, but I would get something like a Mach2 or a CEM120 (budget choice) or the MX+ that mine is mounted on.
So, my recommendation is to just get a fast refractor. Perfect the problems of tilt and focus and then consider if a fast reflector really makes sense or is necessary. Just another opinion.