Mining on the official pool for the past day and now its saying my IP is banned? Has this happened to anyone else?
Yep, for setting too low of a difficulty for your hashrate. Difficulty should be in the range of 10-30x your hashrate (e.g. - 7000 to 21000 for 700 H/s) and can be set by appending the value to your DERO address with a period, e.g., .
Does setting a firm hashrate have any benefit?
You aren't setting a firm hashrate - that depends entirely on the capability of your miner - rather, you are setting a fixed share difficulty so that - hopefully! - you will find shares in a reasonably predictable and consistent amount of time. Like anything else there are tradeoffs involved: the lower the share difficulty the less valuable each share is, and the more of an impact ping time has on your earnings (because ping time becomes a significant percentage of the time to find each share). Conversely, too high a difficulty means you might still be trying to solve a share for a block that someone else found, rendering your share "stale" (ie, worthless).
If you don't set a fixed difficulty - and a lot of pools won't let you because it is misused or abused - then the pool will employ a singularly useless variable difficulty strategy that, in my experience at least, tends to result in spending a lot of time at ridiculously high difficulties for my hashrate (e.g. - 100001 for 440 H/s, when 8000 would be more appropriate).
Note that the format I gave earlier for setting a fixed difficulty does not apply to all pools; some require appending it to your address with a "+" while others require a ":" so make sure you check the pool's "getting started" section rather than solely rely on what some random dude on the internet says.
Huuuuuge potential, HODL! 
