Any new bike you ride, even bikes of the same design, you absolutely should go slow until you know how the bike will react when pushed. It might very well mean different techniques to control your bike, Increase your speed slowly. Any time you approach you limit, Even with years of experience a safe ride can still be a crap shoot depending on how bad you want to win or how fast you want to go.
As far as oversize tires vs suspension bikes go, A big tire bike will react much like a basketball when over inflated. Correct tire pressure is essential for a safe fast ride.
Proper suspension bikes are damped so the rebound is much better controlled. They can often be adjusted for various situations. For most competitive activities I'd choose a full suspension bike hands down.
For recreational riders, Both should be fine with some experience. I do like the simplicity of a hardtail.
Last edited by xroadcharlie; 12-01-19 at 08:50 AM.