A 190 is generally better choice than the 109, if for no other reason than improved visibility and general firepower.
My favorite 109 load out was the G10 13mm cowls, 30mm nose, 20mm gondolas. The problem was that each had its own trajectory and the 30mm doesn't need any help to bring down a target. So, for the G10 I now ditch the gondies and just bring the 30mm.
In a G6 I bring the gondies but use the 20mm nose gun, since the G6 is a pig anyway and the depreciated performance caused by the gondolas really isn't noticed.
In a G2 or F4, I use the 20mm nose gun and leave everything else back at the armament shack. Between the G2 and F, the G2 is the better performer, but the F has the ability to disguise itself as a G10 and catch the turn-n-burn fighters offguard when they mis-identify the plane. My biggest gripe about the F is that I tend to get shot in the back on final approach to land because I can't see the P-51D sneaking up low behind me.
Now, about the 190s, I use the A-8 with the four 20mms. Gobs of ammo and a HO monster. Bomber killer par-excellence. Multiple kill probability. From your list, I'd take the 190A-5 with the four 20mms, even at the reduced ammo load. If you only take a pair of 20mms you'll be short-changing yourself. Don't count on the machine guns to do much work for you. The F8 adds bigger machine guns but also adds armour in places you're probably not going to get shot (also adds wing racks which are more weight and more drag).
So, I'd take the A5. Better guns, better visibility, less control issues at high speeds.
