If you'll be hiking or going regularly to the Boundary water and portaging canoe etc., you will definitely want to have at least a 3-piece rod for ease of carrying and storage while hiking with back pack, canoe overhead, and paddles, etc.(I've been there!). Rods are engineered so much better today than a decade ago regarding ferules (connectors between rod sections) and the rod transition through ferules in no longer much of any issue, especially on a shorter rod.
Purchase a rod/reel combo that will take care of the fishing you will most likely do on a regular basis while going up the learning curve. Redington or St Croix will put you were you need to be, no problem. It may be years before you can even discern the differences between the upper end rods and the combo's. Eight ft. 5 weight sounds about right for trout, medium bass, and all pan fish, but don't be disappointed if you have trouble landing a 42" northern pike on a 5wgt. rod, but they will be lots of fun while they scream out line half way across the lake before they chew through your tippet. Expect that if you pursue fly fishing with a passion you will gradually build up a collection of rods and reels to suit your needs as you understand what length and weight translate into in terms of casting and fishing. You live in great fishing country, and I envy you your experiences to come in the Boundary water with a fly rod.
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