either way you have to slid to hit the 7 so if you crab claw it your first finger has to slid to the 7th from the 8th and back
it depends how you want it to sound if you like the way it sounds with slides do that way if you want a more clean sound do the wide stretch but either way unless you have 5 fingers you cant hit the 13-11-10-8-7 with out sliding

either sliding from the 13th to the 11th or the 8th to the 7th

it all depends how you want it to sound
like CSchlegel said doing it both ways will help you skills for both but will also let you hear it both ways and then... its up to you