Using 'Normal' Braid as Leader

Hi All.

Whats your thoughts of using 'normal' braid with higher breaking strain as braid leader?

Example: Boss Slick Braid 120lb Braid has same diameter and breaking strain as their 'Leader Line' 50m spools.

So will it be more cost effective to purchase say 300m 120lb 'normal' Braid to use as leader line rather than buying the 50m 'leader line' branded spool?

Same stuff. 50m spools are to cater to folks who dont want to buy 4 or 5 300m spools - big initial outlay,

Thanks Tackle-holic.