sleeping bag or sheet?

I'm going to India during July-August for two months.
I plan to start in Manali, and trek from Darcha to Lamuyuru.
I've been told that renting/buying a sleeping bag in Manali is possible, but I was thinking of brining one from home.
on the one hand, ill be more flexible with hiking, but i still am not sure how useful will be outside of the specific trek.
and on the other hand, i dont know how much of a pain it will be to shlep around the whole time.

id be glad to hear peoples opinions and experiences.

thanks,
Eitan

I can't speak to the sleeping back rental - but I do know many people who bring their own bags with them (usually thinner) for use on the train. I got a set of sleep sacks made (basically a double sheet sewed up the side) here, and have yet to use them (the sheets on the trains are clean, and if a cockroach is going to climb into bed with me, it will do it either with a sheet or sleeping back). If your sleeping bag rolls down tightly, you may be able to secure it with compressions traps under your backpack, or in it.