I've read through this thread with great interest, but like @Al Krow I'm reluctant to spend well over £500 on a wireless system. And I can't really avoid mentioning to @peteb that the weakest link in my chain is ... erm ... well, me actually.
With my rock'n'roll band every gig is a doubling gig and I need something different to be happening at the amp for double bass and electric bass. That means that wireless solutions get doubled, doubled in number of units, doubled in cost. Much as I'd like to go the Shure route, buying two of those buggers is a bridge too far.
I've had easily the best results (out of the many, many solutions I've tried) with the X-vive U2 units. They're cheap enough that running two pairs of them isn't much of an issue, the rechargeable batteries are always good for a 3-hour gig plus encores with much-reduced 'green' issues, they're tiny and really simple to use, and they work just fine at 80%, maybe 90% of the gigs I play.
But every now and then we get something like last night. The editing here is designed to draw the viewer's attention away from the issue so watch for me getting all distracted.
At that point we were 35 minutes into the first set and there had been no issues at all. So what happened?
Well we can't know for sure but I did notice that a group of half a dozen youngsters came into the Club pretty much then and sat quite close to the band, mobiles in use. An easy finger to point but I don't recall anything else changing.
At the end of the set I shifted to cable leads for the rest of the gig, and this morning I put a Line 6 receiver that I had knocking about (once owned by @PaulKing) on my pedal board so that I can shift over to it mid-set if it happens again.
The combined cost of both sets of X-vive stagebugs PLUS both high-quality cable leads PLUS the Line 6 wireless unit is still less than the cost of the Shure ...