Dean,
You have raised the right question here. It's very clear that MPPT is better than PWM. Just as it's very clear that a Rolls Royce is better than a Ford. So why doesn't everybody drive a Roller? Answer - cost.
I think it is highly likely that Option 2 will give you more usable amps over the year. I can't be certain, because it is impossible to find real comparison data anywhere, and because a lot depends on the weather.
BUT, advocates of MPPT controllers say they are UP TO 30% more efficient. (Note the "Up to"). So, looking at your choices, lets downgrade the wattage of the PWM package by 30%, and we get 1020*.7 = 714 watts, which is still more than 680, and at a saving of £70.00
Now in fact, we shouldn't use 30% when going the other way, we should use 23% (100% + 30% = 130%, and 100 is 23% less than 130). This gives a wattage of 785, not 714, which strengthens the case for PWM. BTW, 130% of 785 = 1020.
Of course, there are other considerations. You will pay more to mount the extra panels, and also you may not have room for them, You may be able to use the panels in series with MPPT, which means higher voltages and lower currents, and therefore smaller cables.
There's a lot to think about, but one thing is clear. MPPT offers benefits over PWM, but at a cost. Sometimes, as is probably the case here, the cost will outweigh the benefits (in financial terms, anyway). Those who blindly say that MPPT is always the best choice have never done the sums.