The twin will always have a slightly "different" tone, but the cleans on the Lonestar are very close, you may even like it better. It's equal in quality, just slightly diff
I have the LSS which is a different amp altogether
I also have a reissue twin, it's my favorite clean
but I recently went to a Mesa Boogie clinic where Andy Timmons was demoing the LSC and the tone was unreal. I got there early and he was dorkin around on the clean channel, and I'm thinkin, that was that Texas tone is all about (turns out he's from Texas)
He also played a lot of higher gain stuff, and this amp is extremely versatile. Has versatility over the twin, big time
If I was gonna limit myself to one amp, this would be it