I have won our monthly Hassloch with RUG Tempo.
4 Delver of Secrets
4 Nimble Mongoose
4 Tarmogoyf
4 Brainstorm
4 Daze
2 Dismember
4 Force of Will
4 Lightning Bolt
4 Spell Snare
4 Stifle
4 Ponder
3 Flooded Strand
3 Tropical Island
4 Volcanic Island
4 Wasteland
4 Wooded Foothills
Sideboard:
4 Red Elemental Blast
3 Spell Pierce
4 Submerge
4 Grafdigger's Cage
The sideboard was a suggestion by Oddball and I wanted to test it and see how the Cages were. You basically win harder against Reanimator and Dredge, but at the same time you'd die to Life from the Loam. Despite having won the tournament, I have to admit that RUG Tempo is probably not the best choice at the moment.
However, I think I might be able to adress some points made here:
Playing Countertop as a SB option:
This is just a waste of slots imo. I have no idea how the list with Countertop in the SB looks like, but iirc, it plays 4 Goyf and 4 Snapcasters maindeck and 3 Balances in the SB which makes it 11 CC2 cards and maybe 4 Spell Snares to counter CC2 spells. This is simply not enough to concequently counter CC2 spells postboard. Against the classic list as shown above, I'd take out 4 Spell Snares and 3 Ponder for 7 REB/Pierce and that's it. I fail to see how you'd ever want to win a Counterwar against a build that SBs like that.
Counterbalance is decent against Combo and Burn, but combo can easily be won without Countertop and Burn is a niche deck (I believe the matchup is better now that you have a faster clock in form of Delver).
Running Spell Pierce maindeck might be an option, yes, but cutting Stifle should not ever be considered. It's sometimes a bad topdeck when you are losing anyways obv. but I fail to see how Pierce is better in that situation.
In some matchups, Stifle is just key, especially against Nic Fit to stifle Veteran Explorer, Pernicious Deed, Liliana of the Veil (I mean the Edict-ability. Ram that creature into her afterwards or Lightning Bolt it obv.) and sometimes Eternal Witness that could bring back something badass like a Zenith or whatever.
Even against Loam-based decks I'd rather have Stifle instead of Pierce so I don't get wasted out of the game during the first few turns.
Not to mention other frequently played cards that get hosed by Stifle like Snapcaster, Stoneforge Mystic, Hive Mind. It's pretty difficult to find a deck where Stifle is completely dead.

