Well, since this one's been resurrected, I'll throw some knowledge.
I don't shoot IDPA, but I shoot IPSC/USPSA. In that case, a HiPower would either fall into Limited Division, Minor Power Factor since it only shoots 9mm. You could also load it to only 10rds and shoot in Production Division. In either case, magazine safeties may be disabled.
Crimson Trace Lasers would put the gun in Open Division, if they're legal. Open allows red-dot sights, but I don't shoot or have any intention of shooting Open, so I'm not really familiar with the rules there.
As for being feasible to shoot, absolutely. I've shot a Beretta 92FS in Limited/Minor, just like a HiPower would. It puts you at a slight disadvantage in points against other Limited shooters who are shooting Major Power Factor. Minor scores fewer points per hit than Major, but if you make all A-zone hits, they score the same. 9mm forces you to shoot better and get your hits.