puchase from composition and sell to customer

Yes. total tax gets reduced....

No. No benefit to Customer and also dealer.

Bcoz,
Composition dealer's bill is greater than Regular Dealer bill.
Ex: Composition dealer A Purchased goods from Registered dealer Rs. 1000+180=1180
Add Margin Rs. 120 + 1180 =1300
A sell to B Rs. 1300
B add his Margin Rs. 200 + 1300 = 1500. (all are example rate)
Then customer ll be buy Rs. 1500.
It's over cost the goods. So, End user ll be pay upnormal value from purchasing Composition Dealer....

it depends on the rate of tax and profit margin.
if these both are high then only it is beneficial to customers.

Mr. MODI Sir,,
Any tax items is high above said way. Exempt items considering that way. But, Other taxable items also rate is high to customers from composition dealer.