so here is just my little review/opinion of these two lightweight contenders. First off, I absolutely love both of these reels, but I think the Core is slightly more refined than the MGX. I believe this because when they are in my hand the Core seems slightly more solid and isn't noticeably heavier, even though the specs state that the Core is only .1 oz heavier. The Core and the MGX are both very smooth, but the Shimano A-RB bearings seems slightly smoother than the HPCR bearings of the MGX. both of these reels cast extremely well and do not require a lot of setup beforehand, the MGX's dual brakes do there part well, and I actually like the ability to adjust the MGX's centrifugal brakes by turning the switch and not having to undo the side plate. The one thing I do like better on the Core in the spool control area is the cast control knob; on the MGX the knob never really seems to tighten down the spool until you really crank it down, the Core's cast control knob just allows for smoother adjustments than the MGX's clicking knob. Both reels have smooth drags, however the Core's drag system seems to have more lockdown power than the MGX's, even though the MGX boasts 12 lbs. against the Core's 11 lbs. Both reels are rated to handle braid, but I have not tried braid on them yet.
As far as comfort, they are tied, both reels feel exceptionally comfortable in my hand. However, I do like the MGX's EVA grips over the hard rubber grips on the Core. If it is looks you are after the MGX wins in this category, I personally love the Carbon fiber handle and how it plays really well into the overall style of the reel, the Core does look good with the red accents but it doesn't really stand out in looks, from some other reels out there. Overall I rate the MGX a 9/10 and Core a 9.5/10; both are exceptional reels, if you are looking at purchasing one of them, you really can't go wrong with either. Here are the Specs on the two:
Shimano Core 50Mg7
weight: 5.5 oz
bearings: 8 S A-RB + 1 A-RB roller bearing
tapered levelwind insert
7.0:1 gear ratio w/ HEG gearing
dartanium drag w/11lbs of drag
recessed reel foot
audible star drag
1/8 turn VBS side plate
Abu Garcia Revo MGX 7.1:1
weight: 5.4 oz
bearings: 10 HPCR + 1 HPCR anti reverse roller
7.1:1 gear ratio w/ duragear brass gearing
carbon fiber drag system w/12 lbs of drag
x-craftic frame
recessed reel foot
clicking adjustments on brakes, cast control, and drag
carbon fiber recessed handle
Hope this helps anyone with a dilema on their mind, tight lines -Alex