Amsoil XL 5W-20

[Sodium Duck]

I bought this and did my oil change a month or so ago, it was the only one they had in the store so I snagged it. Amsoil XL 5W-20.

http://www.amsoil.com/storefront/xlm.aspx

I thought this was a full, 100% synthetic, but I think I was wrong. The other products on their page say they are "100% synthetic" but not this one.

So what's the deal, I want 25,000 miles or 1 year oil change intervals dang it! This oil is only good for 7,500 miles or 6 months. Next oil change I'm just gonna go get the 0W-20 100% synthetic - maybe the Amsoil dealer will order it for me.

Can someone (ie. all the fluid technician lube masters that know what the tech. specs on the Amsoil site mean) tell me what exactly the XL series of Amsoil is?