We need to know what year bike you have. I will assume your bike is pre-06. I have had great luck with the polk speakers from EC, but I am using an amplifier. Without an amplifier, I was unable to find speakers that I liked. The biggest problem I found was ohm's. The bikes radio is 3 ohm's and most aftermarket speakers are 4 ohm's. I believe J&M has some 3 ohm speakers you could try, but I haven't tryed them.
My suggestion would be to go with the EC amp kit with Polk speakers. If you don't have the factory CD changer, the amp fits nicely right above the CB in the trunk floor.
My riding buddy updated his front speakers on his 02 with the J&M units. Huge improvement. They are 3 ohms so they work very well with the stock radio amplifier. They sound almost as good as the premium sound on my 06. He was impressed enough to purchase the rear speaker kit from them also. We both have our sirius radio wired to an fm relay from Crutchfield Electronics that runs the sirius output into the FM radio. Sirius receivers have an extra output jack this relay plugs into. The nice thing is that the relay requires no power connection so installation is easy. I mounted mine under the seat. I do not know if XM has the same feature. You may need to use an FM modulator with XM. We then have our Garmin nuvi350 GPS/mp3 player wired to the aux. port. I have XM in my Chev SSR and I just plain like the music selection on Sirius better. I would have it in the SSR but GM is in bed with XM for sat. radio. But that is definitely a matter of personal choice. I know some people who prefer XM.
THANKS FOR THE REPLIES, yes I do have an older 1800 02 to be exact. I perfer not to install an amplifier . So I am going to check out he Sierra speakers. Thanks again for the input.
ps I took your advise and just order the J/M front and rear set
I too decided to choose the J & M front speaker upgrade.
I found that this upgrade is well worth the dollar value. So much so that I changed over the rear speakers to J & M.
These speakers definitely compliment the stock system, and I believe that most riders will appreciate the vast improvement.