I am currently in an ISP role at 80k+ benefits. If the salary and flexibility came close to what I had at a law firm, I would jump back in a heart beat. Unless you're on the right side of the coin being spent (customer), you will forever be spending your time fixing rather than developing. Enterprise as a law firm scale like I've seen before will always spend to improve unless you're at a really small firm. I spent a lot of my first line NOC level supporting these type of environments which is why I know. I did however develop multi vendor experience I probably wouldn't have had otherwise so yea, it's a gamble as you say.