Overall, MilSig produces excellent quality paintball guns.  Their markers are also probably the most realistic magazine-fed guns on the tactical scene.  Problems with MilSig markers are rare but do happen occasionally.  The problem with MilSig is not their guns; it's their company and lack of customer service.

Milsig is located in Canada; this is why it can take up to 3+ weeks to get one of their markers (or anything that comes from their company).

With the exception of top of the line tournament style paintball marker, most paintball guns are semi-automatic.  This means one ball comes out per trigger pull.  It also means your gun will shoot as fast as you can pull the trigger!  In case semi-automatic isn't fast enough for you, more trigger options are available as an upgrade for most paintball guns; these are called electronic triggers.  Most e-triggers offer at least 3 firing options, semi-automatic, 3 round burst and fully automatic.