Hi Warp,
just my opinion, but your comfort / confidence level with your current bow would be the deciding factor for me. I would recommend starting off by purchasing some carbon arrows and the appropriate rest for these arrows and shooting them through your current bow. The carbons, although lighter and faster, are denser in makeup and will provide you with as good as, or better, penetration than the current logs you are shooting.
Like you, I am usually hesitant to change bows when I get comfortable with one (currently shooting a 2000 model Martin JagMag with Beman ICS CamoHunter 340 shafts). A good place to deal with to purchase the shafts is online at Mountain Archery where I recently purchased a dozen of the shafts I use cut, fletched and inserts for $40. A cheap way to see what you like. Should you decide you want to try a new bow, I'd probably have to go with a Hoyt Cam and 1/2 bow. The MagnaTec is on the lower level of these, but they are quiet, smooth, fast and forgiving. Quiet and smooth top my list of priorities... There are a lot of good bows out there. I have shot the new Matthews, Archery Research, and BowTech bows (the top-of-the-line...performance and pricewise) and the Hoyt's are very close in performance, but shorter in price, unless you opt for the top-of-the-line Hoyts. Try your current setup with the carbons and you can always transfer rests, etc. to a new bow and then be out nothing.
Again, just my opinion.
BowMan