Get yourself a nice lightweight amplifier. Get a couple of them. Amplifier power is cheap these day.
"Subs" do not require high fidelity, even so all power amps are sonically identical, As long as you match gain.
Read the specs, see the tests, any differences are far below any human hearing. Especially if it's for subs.
Big and heavy has no relation to how well the amplifier performs.
Crown and JBL are both Harman. The make good solid reliable pro gear. Their lower priced amps are also pro. It could be a long discussion about the differences but it's not sonic properties you pay more for.