1. Fit
The differences in fit between EG lasts are not much greater than the variations in manufacturing tolerances between individual RTW shoes, combined with the differing fit characteristics of diiffering shoe styles. Arguably less.
So my 202 oxfords are roomier than I like in the heel (though not terribly so), whereas my 202 derbies are better, because of the higher and more flexible lacing. My 88 E-width chukkas (I usually take a C or D) likewise are a tad large on the heel until they are laced - at which point the high level of ankle support compensates for theoretical heel slippage. Conversely, my B-width 82 derbies are wearable precisely because I can leave a little more space between the lace-holes than on an oxford without it looking odd.
2. Blobby vs Sleek
This is as much a function of style and colour as last. Dark colours look heavier than light. Brogueing adds an extra layer of leather, and any decoration adds "visual weight".
So of my otherwise identical (last and size) brown and black Malvern full brogues, the black ones look less sleek than the brown - indeed my black Chelsea balmorals look fractionally less sleek than my mid-brown Malverns. Of my identical quarter-brogues on the 202, the mid-brown suede look sleeker than the brown calf. My Farringdon's on an 82 look almost Italian-sleek. Whereas my black half brogues on a 202 are blobby-looking enough to be mistaken for Church's. And so on.
3. General
A. Your feet are possibly the most complicated and most individual part of your body (no sniggering at the back please). The answer to all these "last X fits me, will last Y" or "I take a 12.5G in Berlutis, what will fit me in Allen--Edmonds seconds" posts is no-one really knows, except you when you try a specific pair on.
B. Photos on the interwebz are a rubbish guide to the detail how a particular pair of shoes in your size will actually look on your feet. First time I saw a pic of the 888 last I was in love - what a cracking last. Then I saw them and tried them on and thought, yeah, they are actually just a little bit too square for my liking, I'll stick with the good old Fosters 88.
82 
So far I wear the same size in all EG lasts I've tried except the 888 which can be tricky. The black pair were too big. The burgundy too tight, until I broke them in, same size. YMMV next pair will be on the 606 and I'll update then.
