Guthans Takes up 4 inv spaces (5 if you have a shield and weapon), Bones to peaches takes up 3 inv spaces, Not sure why you say peaches takes more space =\, If you train at bandits (which will be the perfect place to use this spell), Ull see that bandits wont hit alot even with full rune, By the time u collect the 20+ bones youll most likley still be full hp, now you turn them into peaches, and now you have full inv of peaches and it only cost about 600gp, That money you use to repair guthans can be used more usefully by buying nats and runes, Who cares about the defense guthans gives you, When u use guthans you use it just to heal not to train so that shouldnt matter =\, If i had the spell i would literaly stay there for days with out losing my spot.