I had space bars on my rigid mt bike til I read that some folks have broken theirs jra on mtbr. (do a "space bar" search on mtbr) They're also listed on the origin8 site as "urban" bars. Take that with a grain of salt. They were only on the bike three weeks before I swapped them out with some misfit fubar's. They're a lot more burlier than the space bars. Another alternative is the groovy luv handles but there's a lead time on those.
I still have the space bars and I might transfer them onto my commuter. They're pretty ergo-comfy but I'd rather have peace of mind when I'm riding on singletrack.
ymmv...