That sled will be fine. As for your expectations of what to see from it... You'll find the suspension lacking in major moguls. Those years the engines started to get enough power that you'd be banging over the bumps. Suspensions weren't designed as well as nowadays and you would just "bang" bang bang over the moguls. The shocks were designed to take some punishment away from your body but still it wasn't great for a ride and you'd be sore after a 100mi day. Now we can ride 200 or more miles and still have a body left to want more. As for reliable, they had lots of the bugs worked out by then so that shouldn't be a problem. Any mechanical breakdowns that's different and things do just break. Otherwise run fresh gas so the carbs stay clean and drain any old gas before riding it. PUt it in the truck instead. I'd put only premium in it too to help protect against detonation that may occur. New plugs and make sure the belt is good and you have a spare. I think it uses the 020 belt on it anyway which is a dime a dozen.
good luck and have fun!
good luck and have fun!