So, in case this was still in question for anyone, I've played around with my respecs (since I've had some anyone from accessions) and I can definitely confirm that although clone is better before you ascend, with mutations added into them, swarm warp definitely becomes better. I don't know what the actual break point is, but even at just 100 million mutation warp is better. So. Yeah.
I'd do the math, but I'm not really competent to actually break it down. But it makes sense, since clone is only exponential until you reach the cap, then its a linear gain, whereas swarmwarp is always an exponential gain on meat units because of how they work. Actually, one sec.
The number I see is 100000x you're production, before bats and clone mutation, for clone larva. That's about 28 hours worth of production, ASSUMING you have enough larva/cocoons to always produce that max. That's the kicker there, I think. You need to effectively "waste" larva in banking up for Clone. Plus, you can cast warp 6 times to a clones one. Based on my math, swarm warp starts edging out Clone Larva, base clone larva, when it hits the 6 hour mark. And at that point its pretty much always better, unless you have absurd amounts of larva, as it also lets meat units run for that time. Again, with the caveat that I am probably doing the math wrong.