eCommerce Merchant Needed- 2CO, PP, 1SH, ???, Who Should I Use?

*What's the best eCommerce merchant to use?*

Hi this is my first post but I've been 'perusing' for a about a year.
Finally getting my own site up, looks pretty sweet I think! I've got a few sites I make money on, but they are all company template-replica-type sites with no control over content, metatags, etc. This one is MINE! I'm pretty stoked about it, cuz I've been dragging my feet buying one thing after another and not doing anything about it for a good few years now. Just within the last 2-3 weeks I actually started taking action, and now it's really coming along (quickplug) ArmoryShoppe dotcom ...SWEET!!

So my dev'r tells me I need to get a merchant. What do you guys know to be the best, or some of the best, and why? Could you please tell me what's good & bad about different merchants?

I've heard of using Paypal, 1ShoppingCart, Authorize.net, & 2CheckOut, but I know there are many others. I know Andy Jenkins is running YahooStores for his eCom site, but I didn't go that route with mine. I know the Rich Jerk recommended one one time, but I don't remember what. I think it was free. (Ya ya, its RJ, but watev. He put out some really good content. Too bad I cant find it anymore, so cant reference to it. oh well, whats 10 bucks for another one, right?!)

I'm just wondering what all the pros are using, and why they are using 'that' one & not another?

Thanks,
Cheers!
-JR Peppar