I have been using the 81-7 for a few years now(although mine is an earlier issue with the extended housing). I have it installed in a Schecter Damien 7 which I use as my primary guitar for practice and home recording. I find that this pickup is great for this type of application as it cuts down a great deal on the amount of noise you get with computers and TV's in the room. At home I play and record using a Line6 Pod X3 and the EMG's are great for low volume playing. I have also used that guitar live but the pickups give me A LOT of feedback at high gain/volume settings. Right now I have the 81-7 in the neck position with a 707 in the bridge. Since the 81 has a greater mid range voicing it tends to sound very well balanced and clear at the neck while the 707 provides slightly sweeter tones at the bridge. The 81-7 can sound very flat or even harsh at the bridge depending on what kind of amp you are using. No matter what position, I do recommend doing the 18 volt mod if you use EMG's(google it). The increase in power is really noticable and it essentially gives the pickups the dynamics of passive pups while maintaining their active gain character. EMG's are actually designed to operate at up to 27volts but 3 batteries is just not practical in most cases.

Let me start by saying I've owned 5 seven strings over the past 7 years. 3 Ibanezes, 2 ESP's. I recently got a Viper 407 with this pickup in the bridge position and I have not been happier with my sound then I am now.

I play with the Low B drop tuned to A so this is hard to get clear without mud. I've tried, Stock Ibanez in both my guitars, Stock esp pups, and EMG 707's and these. These are so far the best I've heard. Clear and heavy without the mush.

I'm gonna put them in my other ESP.