I have a Stumpjumper m2, I would say they are worth buying. I wouldn't suggest them if you are getting into serious off-road or downhill trails but let me explain why.
Mountain bikes are expensive, but there's also a lot of trails these days that older mountain bikes probably don't belong on. You do get what you pay for usually. For something to just get you out into the woods, it's a fine option.
I do take mine off road, there's some trails near my house that are part fire roads, part single tracks, plenty of elevation. There's also trails there that have jumps and other stuff that's more advanced. I don't take this bike down those. Maybe I need more skill, but only having 100mm of travel in the front only plus v brakes isn't a recipe for success going down some of those lines in my experience.
The Rockhopper is going to be very similar to the Stumpjumper. I think many on here would pause at the idea that you wouldn't be able to get the rockhopper back on the trails but rather get the stumpjumper and not have the same situation in a year or less time. Doing offroading is going to require maintenance and things will break and wear out, just like any hobby. So there's going to be cost no matter what, and if you replace a bike every time one gets a little worn, you're gonna cost yourself more in the long run.
350 dollars buys a decent amount of replacement parts and labor. I'd be very surprised if it cost more than that to get the Rockhopper feeling like new, barring any major damage to the frame or wheels.
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