Yeah, might be an issue if wizards surround the Jedi and start blasting. However, there are plenty of examples in the movies of Jedis blocking shitloads of blaster shots coming from one direction, so in a one on one confrontation a Jedi would probably have the advantage there.
There was that one time that that one guy said there's no blocking the killing curse, sure, but then later on it was blocked with physical objects (by Dumbledore in his fight against Voldemort in the Ministry, with those statues) and by magic (Harry blocked one aimed at Mrs. Weasley with Protego, Bellatrix LeStrange blocked Mrs. Weasley's killing curse aimed at her). Then there's all those fights involving Death Eaters where they didn't just mop up the competition with no problem, which they totally would have done if the killing curse was unblockable. Just the blockage by physical objects would be enough to mean lightsabers could stop it, but I'm inclined to say that Force shields would also be able to do it because it's basically a form of magic. So much for unblockable murder spells, eh? 8D