My favoured option for the second Cv element in my Later Carthaginian army is Ancient Spanish II/39's Cv General, an element that is described as three 'long shield' Iberian cavalry minis. For this I'm using HaT's Punic War Spanish Cavalry (8055).
In comparison with the Carthaginian Command these minis are a dream to trim out and assemble. The mould does have some minor errors, creating an extra rim around each shield and an uneven join that shows up clearly on helmets. But the plastic is softer and trims very easily.
The main problem, and it's easily solved, is that HaT issue around 2 caetrati (buckler) riders per scutati (long shield). I'm given the choice of having three very similar riders, or a simple conversion. I opt for the latter. I head back to my spare shields bag and fish out two more of the old Esci Barbarian shields, this time the more oval shaped. Cutting off the 'grip' each has to attach to a hand, I have two correctly-shaped shields with a hole in the middle where the boss should be.
I use the same latex caulk that I use for basing to mush that shield onto a suitably trimmed-back small shield on the original rider. It's not beautiful but effective. Later once the caulk is dried I add more caulk carefully shaped to become the missing shield boss.
I decide to leave the one original shield pretty much as is, because my experience is that if I trim to remove the moulding problem, the rim looks wrong.
I use the same black-varnish basecoat technique as before, this time not trying to do too much detail. These are small minis so less is more.