comparative and superlative

We interviewed 100 customers for their opinions on Mega Books. This report summarises the survey's findings and suggests what can be done to make Mega Books a better bookshop.
Most customers found the books at Mega Books cheaper than those at other bookshops. Eighty-two percent said that buying books at Mega Books helped them to save money.
The special offers are greatly welcomed by customers. Ninety percent of them felt that Mega Books's special offers were the best bargains in Hong Kong.
However, a number of customers thought that our service was not good enough. Over sixty percent of those interviewed found the service worse than that of other bookshops. The overall rating for service is much lower than that for special offers.
A number of customers are also not impressed by our advertisements -- they gave these the lowest rating of all. Only a few people thought our advertisements were better than those of other bookshops.
The findings show thaw that we must improve our service and advertisements if we want Mega Books to become the best bookshop in Hong Kong.