Which gas block to buy?

[xagent]

I have a Delton/spikes 16" flat top AR. I need to replace the front gas block and was wondering which one is the best choice. I'm thinking of the Yankee Hill which is a gas block with a built in flip front sight and bottom sling attachment and bayo. attachment around $90.00 or a bolt on railed gas block and then add a detachable front flip down sight. I would imagine it would be around the same price point. I'm not looking for a high end setup since my rear sight isn't the best. I'd just like to have the ability to use iron sights or take them off if i want to use a scope.