I'm on the same boat here :) Planning to order a Wildcat, I guess form Precision Airguns and Supplies (not yet decided) I see they offer the Hugget but it has to be attached permanently: "We must have your rifle in shop to permanently bond Hugget to rifle." The extra length is considerable, so...
Since the Carbine + Moderator model is longer, I guess it will make sense to use the longer air tube/reservoir and have those extra shots. Any idea if Pyramid or anyone else will be selling regulated, rifle-length air tubes?