This is why I joined a Country Club here in No. Virginia, when I first moved to the area, I couldn't believe it took me 5-5.5 hours to play 18 holes on the weekend. That lasted a couple of summers and then I took the dive to joining a Country Club, which for me is well worth the cost.
I went through the same experimentation phase with my "standard" clubs when I first began thinking about single length clubs a couple years ago, and as @inthecup mentioned, the results were not good -- the gaps were not good, the swing weights were different (because the head weights were different), lies were wrong, etc.
But, I saw enough of an improvement in ball striking (i.e. not hitting fat as often on the long irons) that I tried the Pinhawks (ValueGolf).
Aaron @ Value Golf has been selling Pinhawks for a couple years, but increasing demand for single length irons seems to outstrip supply occasionally (resulting in stock-outs). So if you're serious about trying it, sooner would be better than later -- I recently had to wait 30 days to send a contest winner their iron heads because they were completely out and were waiting for their next manufacturing run to be delivered.
That sounds less like a slow play issue and more like a no play issue. I'd imagine your guys plopped down somewhere for a late afternoon picnic. They probably engaged in a few ball-hunting expeditions and may have taken a swim in a water hazard.
Have been using one for a few months now and love it. Has taken about 3 putts off my normal putts per round average. Where I see the biggest difference is with my lag putting. Has not made any difference with short putts, but I tend to miss the center of the face on longer putts and I have noticed a pretty significant difference. The ball gets closer to the hole whereas my old Scotty would spray it further left, right, or short. I am very confident it is giving me a chance at less 3 putts which was the biggest reason I bought one. Its a very legit putter. Worth trying out, but absolutely make sure to go to someone who knows how to fit for a putter.
I usually play munis. I try to have no time expectations (or for that matter, game expectations lol) when playing golf. I leave my house 45 minutes before a round, and usually get home 5 hours and thirty minutes later. 18 holes is anywhere from 4 to 4.5 hours.
If I have later appointments I book golf earlier.
Over the past month I have invited a new person to golf on two separate occasions. (we are not trying to grow the game, just have an enjoyable outing with family or friend) We planned only 9 holes. Walking 9 holes and flailing at a little white ball tires a new comer. They have no idea of what pace of play means. We explained it and played pick up the f-----g ball if we started losing contact with those in front.
We have a local 9 hole muni. It is often populated by occasional golfers. It is rated as intermediate difficulty. It is often slower on weekends and holidays. If I want to play there I either pick a different time or smell the roses.
If its two non golfing couples playing in front of us, I smell the roses. They have no clue what pace of play means, nor do they care.
To me "golf is too slow" sounds like road rage. Golf is not instant gratification. Never has been. Need will be.