I swapped my tourguards for Schwalbe Marathons (1.5). They roll well as they can take a high pressure and I have had no trouble with grip (except once, on some black ice last winter, but I don't think anything would've kept me upright on that - I just should have seen it eariler!). Most important, I have only had one puncture when using these tyres, and that was on a pretty worn one. If things are still bad and you don't mind the extra weight, the marathon plus look completely puncture proof, with a phenomenally thick Kevlar belt.
More recently I have used the marathon XR (1.75) which are good off-road, and at least as puncture resistant as the regular marathons, but very heavy and roll slowly so no good for regular commuting.