I have never used it but hve heard of it. Yeah a lot of NRI's (non residental indian's) use it to travel. I have not heard any bad stories about it. You should be ok. Why dont you just hire a taxi, much more comfortable all the way to Ludhiana. My friend came to India for the first time and got a taxi straight from the airport to Punjab and came home and sleapt. I think he paid around rs2000. This was you can travel at your own will.

But if you are serious about this Indo bus thing then I can ask around fro you and then give you some advice.