don't cheap out on chains or brakes. I have been running the DIDERV for 10 years on a couple of 996's, a 998r and even on my 900ss/sp. The DID will hold 160hp with ease and last a whole race season, or forever on a streetbike. my2$
Another vote for DiD, but, if all you're after is a gold chain for the street then the ERV3 is overkill...especially for the price! That suckers expensive. Another vote for not getting the ERV3 for the street is you will get more mileage from one of the other chains designed for such. If it's a track bike or you got the money, disregard and enjoy the bling
I have this kit on my bike for the past 4000 miles including 9 track-days. I don't have any issues with it (so far). I am thinking about getting that engine casing guard from motowheels, as a just-in-case deal.
None of the DiD chains are bad, and any of them will handle a 749 also. The best one for the street is the ZVM2. I even have that one on my 749 track bike. The 525 in that one is strongerthan the ERV but don't remember about the 520. The ZVM2 will have much longer life on the street as well cause that's what it's made for.