Firehawk , Nighthawk, Carolina Cobra, and Expedition Everest are good. Thunderhawk is a decent SLC, as is Golden Wings in Snowfield which was at Happy Valley Beijing China. I did get to ride a knock-off SLC that wasn't that bad (By Vekoma standards)
Most SLCs I have ridden have sucked with the exception of a few. I think Invertigo at Kings Island and Stinger at Dorney suck. Any Boomerang coaster without the new restraints is not pleasant. The worst are Ninja at SFOG, Ninja at SFSL and Goudurix. (That I have ridden) I did ride two knock off SLCs in China and one of them gave me a migraine (It was crawling through the last inversions and turns yet still managed to injure me \ ). The other wasn't horrible, but it still was bad.