OK, some info that might be of general interest.
I'm mining with 4x1080ti & 4xVega64. Obviously the former outrun the later by at least 1/3.
Have tried grinmint & sparkpool, and successfully withdrawn my balance to my grin wallet via email txt from both pools.
In sparkpool if you bind to an exchange you can't change it back to email withdraw. You also have to wait 1 day for the balance to mature of course - and only then you get the withdraw button appear.
In grimnit, as soon as it matures you can withdraw.
f2pool I haven't tried - rather high minimum withdraw, + I don't think it's better in any way.
I get a lot a 'bad' shares when using the TLS port on grinmint.
Sparkpool reports a much higher graph rate than grinmint, has good response, and zero bad shares - only a few delayed.
I have tried to mine c31 instead of c29 as it seems the rewards are much higher.
Have not succeeded so far, because from what I understand c31 would work only with grinminer & linux.
Although I read "it is not implemented yet", I see it's live on pools.
If you try the port for c31 (pool port), shares are found but not submitted.
Currently mining on both rigs on Windows 10 64, CUDA 9.1 with Ace miner. It gives a better graph rate from Goldminer (+5%-10%) although it is my impression that the fees are a bit higher than stated (mines fees for longer period of time).
Bminer which as reported has the best performance, I read it's no good above 3 GPU's. Also does not support c31 yet.
Can't be bothered to switch to linux ATM, because I think Windows support is imminent.
Nerd premine as I read somewhere.
Running node and wallet on MacOS.
