[Unsullied_Spy]

If you really want the 40s then go for it. You'll need to gear down to compensate for the size and weight of the tires, you'll go through wheel bearings faster, and it's harder on driveshafts and diffs but maintenance is all a part of the hobby and if you're getting the wheels/tires that you want I'd say it's worth it. I'm keeping the 40 series tires on my Losi Muggy because I think it looks a lot better with them and I like the way the stock tires perform (Losi 420s are basically 40 series with a different hex, and the stock King Pin tires are great!) I haven't had any wheel bearings go bad in the 100+ hours of hard use I've put on it and I've only killed 1 diff and have since done some work to it to make them last better so IMO it's worth it if you really want them.