No matter which gun you go with you should definatly go with a Nitro upgrade. You seem concerned about accuracy and a consistant marker can help with this. Don't be afraid of the mag's poor playing with CO2, becuase if you plan on upgrading to a 'high-end' marker, HPA is a must.

Cockers have appeal because they are complex, and you can upgrade virtually every part. Timing really isn't an issue.

Mags don't look nearly as cool as cockers - however they can be upgraded to a high-end marker with minimal parts. (This, I believe is why Mags aren't as appealing. Its really fun to go out and blow money on 15 different parts, each making your gun a little better. Instead, the mag has 3 or 4 great major upgrades. Wahoo! Not as fun as upgrading a cocker.)

My 2 cents...If you want a great performing gun that is very reliable; go for a mag. If you are crazy about upgrading and tweaking your marker; the cocker may be right for you.

I never regret buying a mag - nor would I trade it for a cocker. It is all preference, and I'm just a mag guy.