Hey, from what I can remember there was no noticeable lag on this TV when I was using it with the OSSC (It’s still in my living room but I’m now using a Samsung KS7000 for my gaming TV). I always thought the picture looked great with the OSSC, it even works on every single mode I throw at it, no dropouts or anything. This is a pretty old TV at this stage, about 7-8 years old? So I hope that if you’re buying it you’re getting it for pretty cheap.
I have to say though, I really like the TV, even today it performs great and in Linex5 mode with scanlines, displays PS1, SNES and MegaDrive beautifully.
Hope this helped!