Bookshelf speakers with the best bass...

Unless you are actually putting them on the bookshelf, a good well matched speaker stand will do more to determine how good the bass is, more than anything other variable. So pick a speaker where you like the mids and highs and then carefully choose the stands.

They say Red Rose 1 monitors have nice 'bottom' extension!

I agree with Sugarbrie, great stands like Sound Org. with sand and lead shot, Blue Tac on top will certainly tighten and deepen bass. For $2500 the Reference 3A DeCapos are superb.