I've never owned a Surge (got to use one when in the army though) but do have some (actually, all kinds of
) Spirits, including the bit kits (ratcheting and L-shaped thingies). The ratchet is what I now carry, but it's not without "issues". First, the ratchet without the extension is practically useless as the reach of the bits alone is miniscule. If you want to go minimal/lightweight, go for the L-shaped wrench. Second, I wanted to use it with LM (flat) bits, and found that the ring holding the bits in the driver was not such a good fit (it would hold the flat bits if inserted a certain way and they would fall out otherwise); I ended up combining the Vic ratchet with LM's bit extender to get the best of both worlds. Third, I've never over-torqued it so I don't have any hard facts as to its structural strength, but being a small ratchet I wouldn't overdo it; if you're dealing with stubborn screws most of the time, I would suggest the L-shaped thingy again.
All in all, if you're happy with LM flat bits and don't want to go the full-hex way, I'd suggest sticking with your Surge, probably adding just a LM bit extender.