A noobish 870 questions RE: barrels and scopes

[knoxtnshooter]

Hey all... new poster, but i've been lurking for a while.

Thinking about buying my first shotgun in the next few weeks and I'm settled on an 870, but not sure what the best course of action would be.

Primary purposes will be HD and also slug hunting deer. I understand that in an ideal world, i would just buy the two barrels that suited my needs individually, but i think i may be able to kill two birds with one stone... or slug... whatever.

Looking at Remington's offerings, I'm leaning toward buying their Express with a 20" smooth bore barrel with rifle sights. I would then have the reciever tapped for mounting a scope... probably with a pic rail. I believe i could use the sights over the pic rail when the scope is removed for its role as a bedside buckshot gun.

However, I don't know everything, so i thought i'd pose the question here. Is a reciever mounted scope on an 870 as reliable as a cantilever mounted on the barrel? Going to a cantilever would throw off all my plans, but if it is necessary i will.

also, is there some combination of barrel/mount that I'm missing here? Thanks.

[SRG]

First of all, before you purchase that Express, take a look at this guy's offerings.
https://www.vangcomp.com/Home.html
You don't need to go to a cantilever setup. I think the cantilever is mounted on the receiver, not the barrel.

[knoxtnshooter]

actually the cantilever is barrel mounted. you may be thinking of a cantilevered aimpoint mount for ARs.

While the VC stuff is really cool, there isn't anything of use to me there unless i'm not seeing something on the site.