How much oomph does the Bryston B60 have?

I just bought a Bryston B60R (through A'gon), and now I want to upgrade my speakers. I started out looking at monitors - the Paradigm Reference Studio 20's and PMC TB2+ seemed like good choices. But then I realized that for about the same money as a good monitor and a solid stand I could get a good floorstanding speaker.

The PMC GB1 or the Spendor S5e would suit my listening tastes (chamber music, choral, some orchestral, pop, and miscellaneous), but would the Bryston be able to drive them effectively?

I realize that most larger speakers will sound better with more than 60 wpc. But does the Bryston have enough power to make these two designs work?

The PMC GB1 is a two-way, but it has a long transmission line. The Spendor uses three drivers, and the company describes it as "2.5 way." (I guess this means the bass driver is a passive radiator.) They both have a sensitivity of 87dB (1W @ 1m).

For what it's worth, my room is medium sized (L-shaped, with one leg about 27' and the other about 25'). I listen at moderate volumes. I'm on the second floor of a two-flat, so I don't need or want earth-shaking bass. I just don't want muddy, ill-defined bass to ruin the other virtues of a larger speaker.

Advice?