Try out the samson audio stuff at swee lee if you are on a budget.
If not go for the Shure ULX, so far works best for me and service good also compared to sennheiser and AKG service which sucks.
the sennheiser ew100s are a good choice for budget users. Has built in frequency scanning as well. If on a low budget why not look at AT(though dun expect shure or sennheiser quality)