It's unfortunate that the "Rate Browser" tool doesn't have the same options as when processing an order. Therefore, since the quoting options are very limited, the quotes are not accurate. UPS charges for insurance for shipments over $100 at $100 increments(about a $1 per every $100). The Rate Browser doesnt have have an options for insurance, so if an order is worth $101 and the obtained quote is for $100, the quote is useless/inaccurate, because once the order is processed, there's an option for insurance, which increases the rate.
Again, a rate calculator can NOT be accurate/complete, if it has less paid options than the order processing tool.