I would vouch for the Jain Shikanji in Modi Nagar. I have been there twice on the way to Haridwar. It is in a class of its own. I also agree that I had bought some for preparing at home, however the taste was totally different from the on emade by them.
My home is in meerut, but i live in delhi (earlier studies and now job in delhi).But i have never missed an oppurtunity to have a sip at jain shikanji while travelling from delhi to meerut or vice versa. Its Paneer pakodas should not be missed with shikanji. Beware of spurious shops, One will find many shops with same name on that highway. remember,the original shop comes after travelling 3-4 kms more from modinagar City