Thinking on changing the speakers, any advice?

[Tetsuro]

Don't wanna go overly cheap this time so I've narrowed two pair of speakers (front ported!) to mate with the new NAD C-315 (40 Watt):

Monitor Audio BR2 (medium-cost, medium size)
KEF iQ1 (high-cost, small size)
PSB: IMAGE B15 (very high-cost, small size)

Which do you like better? And which will go better with a NAD amplifier? Are them easily better than mine actual Energy C-100?

Thanks.