Need a new frame ASAP, Iv been looking at the sunday, but.... what size???

Im just between 5'10" and 5'11", id say that i rode fairly agressively/tecnically putting the bike where i want it rather than the bike taking me for a ride, so im more of a finess than a plow rider but id like to have somthing that will take everything up(not in a plough way) and track well but still alow me to be active on the bike.

I prefer a medium sized bike, but if it comes down to a bigger or a smaller bike id go for the more flickable option...

So, the 16" top tube measures up to most medium bike so does anyone my size ride this size? does it feel realy small and get sketchy at high speeds? or does it feel like a regular medium?

the 17" does it feel bigger than most medium bikes? the top tube is nearly an inch longer than most mediums, do you need this extra length to make up for the short swing arm? does it feel long and sluggish on slow speed/ technical cornering?

Im realy not sure what to go for so id love some help, also has anyone ridden both? was the differench that much between them?

thanks
Adam