I asked guys at Powergrip what they know about SL's, and their opinion is that Pro Starfires are in fact SL's at the moment. They went through all their Pro Starfires; most of them were SL's, one was Starfire and few were marked SF and they were in between of those two. So it looks like there are Pro SL's available. I'll put them into consideration and see if I could maybe trade one somewhere and check it out.
I had SOLF's in my bag in the past, but they were all really hard fading discs, they almost felt like Predators. It may be that I just got lemons, but I don't know. But I think I would rather go with a disc that is more like distance driver, not a tweener like OLF, because if I'm going for control I reach for my Eagles.
I think I've never thrown a Flow. It could be worth trying, at least I've read many good things about them here. What charasterictics should I look for if I decided to test it? Flat or domey, PLH, which plastic?