Re: EMG 81-85 for other style of music
Steve Lukather, David Gilmour, and Vince Gill are the first names that come to mind for non-metal EMG users. I don't hear them and think, "EMG". I just hear great tones because great hands are using high-quality products.
As for the specific question of, "Can 85/81 do things other than metal", the answer is yes. By definition, since I don't play much metal, if I have 85/81 in my hands, they're not doing metal. Whether or not they're the best tools for the task at hand is another matter.
85/81 are essentially just very warm/round and thick high-mid spike humbuckers, respectively, with high outputs. If you seek that voicing and want to hit your preamp hard, that's the route you take.
Usually, though, for applications like blues or roots rock, the playing skews towards lots of dynamics, digging varied tones both out of the pickup and amp. Feel-wise, such a player might not appreciate how compressed 85/81 are, where the attack is almost just on-off. You can pick really lightly with an 81 and let the pickup/amp produce a mighty roar as a result. That might not be desirable in more rootsy setting where if you pick lightly, the expectation is that the result is a light sound.
As a generally rootsy player myself, I like the sound of EMG's - they are great at their job - but prefer passive pickups in terms of feel in response to pick attack. This is probably only perceptible to me, the player, as opposed to any audience. Recently I played a Strat copy loaded with EMGs (don't know which ones), and I couldn't help thinking simultaneously, "These are some of the best Strat tones I've ever gotten", and "I hate how this feels".
I just randomly recalled playing an Ibanez Iron Label RG (marketed towards metal players) with 81/60 pickups, and discovering, to my pleasant surprise, that the middle position yielded a very usable funk guitar clean tone.