While the S9's each ramp up separately, you would be producing more total shares as they ramp up and earn more per block found as well. The ramping up may seem like a hurdle, but you have to remember there is always a "ramp down" period that is equal to the ramp up period. If you ever move machines or unplug them, you get rewards from blocks found after that even when you don't have your hashrate in the pool at the time.
Thanks for your response, this is helpful.
I'm not too bothered about having benefits due to ramp down. In fact, the ramp up is not a big concern for me either, as in general, Im will to point to a pool and just leave it.
My main concern is .. i've tried quite a few pools and have gotten large variances in payout for the same equipment (even what is said on pools estimated data on their websites). Im just trying to gauge the "steady state" payout (leaving difficulty out of the equation for the moment, as that applies to all pools), and which one is best for me to just set & forget.
For the past 5 days, i've been comparing Antpool, viaBTC, Bitcoin.com, Slush & Kano in parallel. Kano is the only one that i'm not able to compare directly.
If the experienced folks here can share some insight as to what reward per S9, i could typically get (based on average luck & diff in the past few weeks) ..... i'm willing to point all my 121TH at the pool.
Go to page 1704 and read the posts on that page. There have been many excellent posts on the earnings subject and this one comes to mind. Also on the home page of https://www.minergain.com/, there is a coins/day comparison between pools that is interesting as well.
Page 1705 was pretty good on the subject of payout comparisons also.