Just looked at the link matey, Not really heard of the brand of the Amp mate, It depends on the true power output of the amp, a lot of the figures stamped on products make it hard to say, nearly all cheap amps dont give out true readings, and to get the most of your sub its best to put a bit of money into the amp and get something thats gonna give the power you need. You have the right idea of the sort of deals to look for. For example for another £100 on Cel-direct.com you can get the alpine deal of the v12 alpine amp and the type R sub. Bridged that will give you 340watts RMS at 4ohms, not massive figures i know, but sound quality will be nice and not too pocket hungry.
Its so hard mate i know as if you speak to the dealer they will tell you and try to sell you something totally different. But sometimes the guys are genuine, do your paper work and check the deals on the net and visit you local ICE guys and see what deal you can get. Remember thou the figures your looking at on the net are generally not RMS power figures, look for that as its more likely to be honest answers.