Titans is the best overall choice, but many people prefer Thunderstrokes for PvP for the -15 enemy res and 15IAS. But I choose Titans for both, because of these stats: 30% FRW, +20 Str, +20 Dex, Rep Quantity + Incr Stack Size.
I have used both and find them to both be excellent Javelins. . .but they both have their place depending on your build.
I prefer the Thunderstrokes for a Lightning build- for a non-Lit build, then go with the Titans.
I use a fully synergized Lightning build, so anything I can do to help my main source of damage hit harder is a good thing to me at least. The only pain is that the requirements-especially dex- are higher for the 'strokes.