The Rift Scuttler is worth 50 gold or 65 gold if the killer has Hunter's Machete. You are screwing your team out of 15 gold if and your jungler are tag teaming it and you take the last hit.

Junglers, the Rift Scuttler is is worth a Siege Minion + a Caster Minion in gold to you. On top of that if you are under-leveled it gives you bonus XP which can help you with catching up. Make sure you are taking those things for the gold, XP, an the vision granting speed shrine.

The ease of taking the Rift Scuttler depends on the champion you are using. If you have some sort of hard CC such as a root or a stun (anything that prevents the Rift Scuttler from moving) use that on it first as it permanently (for the duration of the current spawn) makes the Rift Scuttler lose 50 Armor and 50 Magic Resistance.

So if you are Amumu, Bandage Toss to the Rift Scuttler for the stun to drop it down to 10 Armor and 10 Magic Resistance. Also, try to do as much damage to it as you can while it is stunned as while it cannot move it takes 25% extra damage from all sources.

So using Amumu as an example again. Turn on Despair so you don't waste time activating it during the stun duration. Auto attack it once to get the Magic Resistance debuff from Cursed Touch so Despair and Tantrum do as much damage as possible and then auto attack it until it realizes it is doomed and it dies of despair.

If you have more than one person with you, you can box it by having one person stand directly in front of it and one person stand directly behind it. It will try to path around you, but it isn't fast enough to manage it. It will only run from the first source of damage so you can kite it back and forth between the two of you.

In regard to the Speed Shrine it provides, it used to pretty much grant vision of the entire river, however Riot reduced the vision radius on the speed shrine so that if you walk around the speed shrine circle without crossing the border, the enemy team will not gain vision of you.