Bel Canto E one C5i Integrated Amp power question

Yes on all the time

The c5i should do a very good job to drive most speakers to reasonable spl but not the last word if you like to listen at more uncomfortable listening levels with less efficient speakers. There is a preamp output on the back so very viable to use it with a beefier power amp if desired.  Little more to want or need ever with that combo. 

I had a C5i for several years. I liked it a lot.  As others have noted, whether or not it has enough power depends on your desired listening volume in combination with your room size. (Bigger rooms need more power than a smaller one to reach the same volume.)  Get yourself an inexpensive sound level meter so you can get a solid reference point for your desired listening levels.  I rarely go above 85 dB these days and have no problems reaching my desired listening levels in a 24' X 14' room with a Schitt Aegir which is 20 w/ch 8 ohms; 40 w/ch at 4 ohms and a pair of 88 dB efficient 6 ohm Ohm 1000 speakers (though I do have a powered subwoofer for the low end which takes some of the load off the amp.)

My c5i is driving a pair of kef ls50s these days in a large open family room/kitchen area. The ls50s sound glorious and they are not easy speakers to drive. I’ve heard them sound quite bad/flat on other amps with a lot more rated  power than the c5i in that room.