You're asking about a couple lines from Altadis (RyJ, Montecristo), a couple from General (CAO, LGC), and a number of other companies. You've mentioned Altadis' flagship frontmark (Montecristo) ... General's is probably Macanudo, although they also own Punch, Partagas, etc.
Anyway, a few thoughts, with the caveat that I hardly ever buy cigars at retail:
RyJ (non-cc): The Reserva Real is a decent cigar if you like mild-to-medium Connecticut wrapper cigars. I like the Reserve, which uses a Nicaraguan wrapper & binder and has a little fuller flavor. The Romeo Aging Room is not bad; I thought it overpriced but it sold pretty well at my favorite B&M.
Alec Bradley: IMO some decent offerings of late, particularly the Nica Puro Rosado. I liked the original Nica Puro as well, but the Rosado trades some strength for flavor and complexity.
Monte Cristo (non-cc): They play in a tough price range ... Espada is an OK medium-bodied Nicaraguan, well made but overpriced (see a theme here?).
Perdomo (excluding the Silvio): I'm not a fan of Perdomo and rarely smoke their stuff even when it's given to me.
Camacho (regular production, not the Liberty, etc. and not the aged stuff): The only Camacho I've bothered to smoke more than once since the Davidoff buyout was the Ecuador. Little of their stuff appeals to me. I tried a sample of the American Barrel Aged and couldn't smoke it more than halfway ... bad construction, not much flavor.
Rocky: Nope. Too many lines, too little value.
Gurkha: See Rocky, above. Although there are really two Gurkhas ... the online stuff and the B&M-only. I haven't smoked some of their newer B&M offerings (rolled by Abe Flores, IIRC).
CAO (regular production; not the Odyssey, etc): General Cigar's most gimmicky product line since Foundry. My local shpo got a zillion boxes of Amazon Basin and sent most of them back after they gathered dust ... overpriced and tasted like carp. The Flathead still has me SMH -- not much of a cigar, but great marketing.
LGC (non-cc): The Serie R Esteli is pretty good ... a 6 x 54 Nicaraguan puro, medium to medium plus, at a fairly honest price. IMO as good a cigar value as you'll get from General.