Speaker Wattage Higher than Receiver?

The only real danger from a receiver which delivers significantly less power than
the speakers can handle is if the amplifier clips its output signal because it's
being asked to deliver too much power. IOW, some caution is indicated before
you crank the volume to 11.

If you buy tires for your car that are rated for a maximum speed of 130 MPH, you are not going to damage them unless you drive the car faster than that.

If you use a speaker that is rated for a maximum power level of 250 watts, you are not going to damage them unless you use an amplifier that can put out MORE than that.

The only exception to that would be if you turn the amplifier up to where it is distorting horribly, in which case it CAN put out more power than its RMS power rating (which is maximum UNDISTORTED power). This is clearly audible and anyone with half a brain will turn the volume down before speaker damage occurs.

I would advise you to look at the PSB Image T6 speakers, or the KEF Q900 speakers, which are IMO opinion MUCH better-sounding speakers than the Klipsch speakers you refer to.

Both of these speakers have repeatedly had reviews praising their incredibly good sound quality and describing them as the best speakers in their price range, and I agree with that. The Klipsch speakers are generally regarded as mediocre and overpriced, and you would be well-advised to slow down and do some research on the subject.

Yep. When you hear your speakers starting to lose composure at louder points in music and songs, back the volume off a little bit. This point may vary on your volume dial depending on the input signal of the recorded medium (some songs or movie may play louder). Your tweeters will thank you if you don't clip the amplifier

As for the Klipsch RF-7 II, a lot of people like them for HT use because of their very high sensitivity rating. They will play louder with the same receiver wattage output than many other speakers. Just be sure to budget for the matching center channel from Klipsch.

Yeah, what he said. The amp section is rated at a certain total harmonic distortion (THD). It can put out more but at a higher THD (clipping) which can damage speakers. Even if the actuall wattage is lower than the speakers can handle.

Klipsch speaker have a particular sound that I do not favour but many do and they are well regarded especially for home theater. Have you had a chance to listen to these are similar speakers? If you have and like the sound go for it. The nice thing about these speakers is that they have a high sensitivity. Meaning that it take less power (watts) to produce louder sound (SPL)

FWIW, while Klipsch nominally rates the RF-7II at 8 ohms, it's ancestor the RF-7 was reputed to be more difficult to drive than its sensitivity implied, partly thanks to a less than friendly impedance curve, including a dip below the 3 ohm mark. While I'm unaware of any 3rd party measurements of the 7II, I'd count on some nasty impedance dips, and it could be problematic for your Onkyo.

Depends on what you're looking for. If you're watching a lot of action movies and listening to rock/heavy metal music at 110+dB, the RF-7IIs aren't half bad. I personally wouldn't trade my RF-5s for a pair of Salk Songtowers in my theater. On the other hand, I've got a pair of monitors in my bedroom that I prefer for some music.

For you Center channel, yes it will likely be a problem. For your surrounds, not unless you listen to a lot of music in surround format (multi-channel A-DVD's, SACD's, concerts on BD or All-Channel Stereo).

If you center speaker doesn't have the sensitivity to compete with your Fronts, you could have a problem hearing the dialogue, or your AVR's room compensation software might EQ your Fronts in strange ways to try and get them to match your center (or vice versa).

At the very least try and get a Center speaker that matches well spec-wise (mainly Sensitivity and Ohm) with your Fronts.