my old Laney cab is front loaded, and seems like it might be a bit smaller than a normal Marshall cab. or at least, the speakers seem closer together! either way, those traits, combined with the fact it doenst have cloth on the front (its a steel grill...how much more metal can you get?) tends to make it a bit more present. not necessarily more high end, just different, and its actually a very tight sounding cab IMO, along with having a pretty deep sound. it can thump pretty well, never had a problem handling my 5150 with the resonance turned up (although i usually played with it low), and it can handle my Single Recto just fine. however...
im trying to get a 1984 JCM800 cab from a dude locally. on one hand, i need another cab to leave at my buddy's house so i dont have to transport mine all the time (up and down stairs SUCKS), not to mention being in 2 bands...yea. then on the other hand, its rear loaded, and is obviously going to have a different tone. so what if it works better for one band's sound? who knows...its all possible. plus, it will be fun to be able to hook into 2 4x12s again!
the only downside...the cab has G12m70s. well, not really a downside. they just dont sound really good at lower volumes. i never had a problem with my tone when it was loud and proud. so as long as the cab can deliver the goods at volume ill be happy. if not, ill swap a couple out for some different speakers. i want that cab!