It wasn't any trouble for me. I just paid the guy $80 I think for the full exhaust. He even helped me install it and do the jetting in his shop. I had heard the pipe on his bike a few times before and he got a new full Yosh exhaust. Heck of a nice guy.
If you or someone you know are handy with pretty simple metal working (popping rivets, some cutting and welding, re-doing rivets), it's not too hard. I guess it depends on how easily your stock can comes apart (that didn't sound right, but you know what I mean). Cost is probably less than $50. Maybe a muffler shop could do the work for you and even get the new baffle etc. Still would be less than a slip-on.
One warning, however, is in re-jetting. Becasue this guy had this "system" on his bike for some time and got the jetting right, we knew EXACTLY what to do on my bike (same model obviously). If you buy a slip-on for your bike, it will likely come with re-jetting recommendations if needed. If you create your own frankenstein (what I call mine), you may have to determine proper jetting on a dyno with A/F mixture analysis. THAT may make it more trouble than it's worth. Although even paying someone to do that may still be less $$ than a new slip-on.