Harnesses vs seatbelts

[rpjg1975]

This may have been covered elsewhere but not found anything searching around. In 'the book's it suggests that donor seatbelts may be used rather than harnesses. Is there any major arguments between doing this? Just thinking my roadster will be mainly road use so would get away from both the extra cost of buying harnesses and also the chew on getting in and out of them too.

Welcome any comments

Cheers

Russ