Got mine!! Thanks Rich!

I think I'll wait until next year when its 100+ to change mine out. That way I'll be able to compare the R4 vs Sanden when the TX heat is at full blast. Cruzing down the interstate, the R4 can only muster 62F center vent temp when its 100+. But on days like today when its only 93 or so, the R4 can get down to 50F or lower.
I already have a PF condenser on the car thanks to Yak, so i'll probably stick with 134 as the refridgerant.