If I put origin in the mains and Gosen Polylon in the crosses, would that be an arm friendly setup? I am thinking about 48 lbs for Origin and 45 lbs for polylon in my prestige mid. I want to use polylon just to bring the overall cost down of the string job.
Yes, installing Origin in the mains and Gosen Polylon in the crosses will indeed make for a very arm friendly setup. My only concern is that you are coming from a poly main - synthetic gut cross setup as your default. It might be a big transition in feel going to the opposite end of the spectrum and not everyone ends up liking it. You get great arm comfort, power, and ball pocketing...with a soft string in the mains...but some people simply prefer a setup that bites the ball more (spin potential) and feels more boardy.
What I would suggest is that you first try a poly in the mains and Origin in the cross. You will get improved power and and arm comfort..but still maintain really good spin potential. As many have opined about Origin...it doesn't excel at any one facet...but is a very good string with no real weakness. I actually think it excels as a cross string for some people because of its attributes.
I'm currently using a Yonex Poly Tour Fire - Babolat Origin at 52-54. I actually prefer this setup better than a natural gut-poly setup. I get way more spin potential and directional control is also better. Installing a soft string in the mains is great if your aim is to get more power and ball pocketing...but for me...it's just too much power and there is only so high I am willing to increase my mains before the variance between main & cross (poly) tension becomes too wide for my liking.
I'm not a big string breaker and I find Yonex Poly Tour Fire - Babolat Origin plays really well for an extended duration. Definitely an upgrade over using a synthetic gut in the cross in my view. The one thing I definitely notice about this setup is that there is noticeably more string snap back (spin potential) that is very audible. It might be a combination of the new silicone infused Yonex string working in conjunction with a smooth & slick cross string (Origin) that also provides some ball pocketing. In any case, I highly recommend the setup if you ever get the opportunity to try it out.
Good luck.