Audio Systems: 2 Channel or mono and what brand?, mono amps, mono amp

Question
Dear Mark Lampi,
My friend is selling his Helix Competition W12 Sub to me and it is a vented voice coil (assuming its a single coil because the specs did not have a plural on coil) with 4ohm and rated at 350RMS/700 peak. I read somewhere that it is better to set up a 2 channel amp and bridge them into the one sub. So my question is; Is it true that it is better to bridge a 2 channel amp to a 4ohm sub or will a mono amp do just a find as the 2? Also I'm new to most of this, so I wondering what brand makes good amps. I know the typical Alpine, but I was looking through their amps and generally the 2+ channel amps are way too expensive. I'm looking to spend less than 300 for an amp.

Answer
typcially a mono amp is better for a sub. sometimes the mono amps are too powerful though for smaller systems since they are designed for running only subs. they're also usually optimized for 2 or 1 ohm loads, so a 2 channel amp in bridged mode is more suited towards runining just one 4 ohm sub.  Just so long as you dont try to use a 4 channel amp with a sub (YUCK!).
my recomendation if you are looking for a good bang for the buck (man they should pay me for all the recomendations I do for them) is the power acoustik gothic amps.  The OV2-820 is rated for 460 watts at 4 ohms bridged mono which would be a great match for this sub.  they are only $85 plus $22 for S&H on ebay!  I have them in many of my setups and have heard them in other people's cars and have installed many of them for other people, I have nothing but very happy customers.  
let me know what you think.