SOLAS* retroreflective tape is the brightest at a very narrow reflective angle.
DOT C2 red or white reflective tape is almost as bright over a very wide reflective angle. This is the tape used on truck trailers, etc.
Engineering reflective tape comes in colors but is less reflective.
*Safety Of Life At Sea...the international safety regulations for ships and seamen.
Wear a Class 3 safety "vest" with reflective strips on the body and on the short sleeves. Don't wear a back pack or use a tall tail bag that hides the stripes.
Aim your headlights to put the light as far out as possible without blinding on coming drivers. Consider upgrading your headlight bulb. (No blue bulbs, pls.) Brighter bulbs use more expensive gas in the bulb, better center the filament in the optical center of the reflector, burn hotter for a shorter life. A standard 60 watt high/55 watt low beam H4 bulb for your V-Strom is the max wattage for the stock wiring, but you can get brighter, shorter lived 60/55w bulbs. Phillips Xtreme Power or Narva RangePower are good choices. A wiring harness with relays is a help. The Osram Rallye 70/65w bulb rated at +50% light output is a good choice with the relays.
Keep in mind that however you light up your bike or yourself, present a view that the motorist recognizes as a motorcycle. Spots of brightness here and there won't get the message through to drivers that are tired, thinking about work or home, talking, eating, shaving, etc.